Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Security Media Music

The Sound of Your Firewall 232

upside writes "It had to be done. Once The Spinning Cube of Potential Doom gave us a 3D visualization of a firewall, someone was bound to ask themselves 'What does your firewall sound like?'."
This discussion has been archived. No new comments can be posted.

The Sound of Your Firewall

Comments Filter:
  • Anthem / Midi? (Score:5, Interesting)

    by CommanderData ( 782739 ) * <kevinhi@y[ ]o.com ['aho' in gap]> on Thursday June 17, 2004 @09:13AM (#9452108)
    I really like these concepts for alternate ways to visualize large amounts of data. Reminds me of Douglas Adam's Dirk Gently books. There was a character who wrote a program called Anthem that would interpret a company's stock data and vital statistics and play a tune based on that data.

    Rather than using a Wav. file, maybe this could be written to play a variety MIDI tones to account for all kinds of activity on your network!
    • by Trigun ( 685027 ) <evil&evilempire,ath,cx> on Thursday June 17, 2004 @09:19AM (#9452175)
      Just pipe everything into /dev/sound. Easier, elegant in its simplicity, and will keep people out of your cubicle.
    • Dont forget the Hax0Rs' koan -- "Whats the sound of one port hacking"
    • Re:Anthem / Midi? (Score:2, Insightful)

      by torpor ( 458 )
      My buddy started a company [soniccouture.com] that specializes in custom applications of sound design ... one of the things they did was stock-market 'audio interfaces' so that you could listen to stock and other financial data instead of having to watch it all the time. I can't find the link for the details on this project, but at the time it seemed like they were making real progress on this kind of interface...
    • by pcmanjon ( 735165 ) on Thursday June 17, 2004 @09:47AM (#9452498)
      Once a waterbottle fell over somehow and my router was douched in it.

      I got to find out what a router SMELLS like.

      You know that never-mistakable smell of electronics on fire?

      Yeah, thats what they smell like ;]
    • by quadra23 ( 786171 ) on Thursday June 17, 2004 @10:01AM (#9452652) Journal

      You need this kind of quality to accurately measure the warfare that your Firewall is waging against anything evil on the cyber-waves. That latest Windows virus? Nope got smacked down by your firewall and you heard it about a minute ago.

      Forget games(!?), just listen to your firewall wage glorious battle for the freedom and security of your PC and/or home network(!) in the comfort of your own home! All it would need then is a quality commentary...

      "Firewall detected malicious port scan and DOS (Denial of Service) attacks aimed towards IP 19.5.4.10 on port 70. Access denied, commence lockdown and vapourize all opposition!" Forget those war movies folks, you can experience it for yourself now!

      Or how about "Reinforcements (firewall updates) have just arrived deploying them as according to operating procedures".

      Man, that would be the life, at least now spending hours on your own PC won't be dull again! Only thing left would be to be figure out a way to salute to your firewall and give it medals of honour...Hmmmm, this will take some time to figure out, but at least we got this far ^_^

  • time.. (Score:3, Funny)

    by Ian 0x57 ( 688051 ) on Thursday June 17, 2004 @09:14AM (#9452122)
    where the heck do people find the time for this stuff.... I can think of a whack load more things to do... like read slashdot.
  • by th1ckasabr1ck ( 752151 ) on Thursday June 17, 2004 @09:14AM (#9452123)
    That's all well and good, but what I really, really am dying to know is what my firewall FEELS like...
  • how about... (Score:5, Interesting)

    by wwest4 ( 183559 ) on Thursday June 17, 2004 @09:15AM (#9452128)
    moudulating the pitch on the dropped/blocked port numbers? I bet it could sound like a windchime with the proper modulus.
    • Re:how about... (Score:5, Interesting)

      by digitalsushi ( 137809 ) * <slashdot@digitalsushi.com> on Thursday June 17, 2004 @09:35AM (#9452371) Journal
      Hrm. One of the things I let my server do for me is emulate a giant grandfather clock. Cron plays the wave files. People always ask me where the clock is, but it's just coming out the stereo.

      If I set it up to do quarter hour chimes, that would be a rather interesting way to announce network meta-data: The louder the volume, the more stuff going on that I probably don't want. I could make it two dimensional by using sound and pitch, and I wouldn't even have to do any fancy math stuff I don't know. I could just make 8 different pitches and gradiate using that.
      • You could use the red alert klaxon from star trek - but I guess that might contrast too sharply with the stately ambiance of the grandfather clock sounds, eh?
      • If I set it up to do quarter hour chimes, that would be a rather interesting way to announce network meta-data: The louder the volume, the more stuff going on that I probably don't want. I could make it two dimensional by using sound and pitch, and I wouldn't even have to do any fancy math stuff I don't know. I could just make 8 different pitches and gradiate using that.

        Hmmm, kinda like a Firewall Theramin!
    • My firewall would sound like an orchestra breaking through a glass floor during a pipe bomp explosion.

      (Direct IP on an ancient EDU network.)

  • by Aerk ( 697405 ) on Thursday June 17, 2004 @09:15AM (#9452136)
    This wall sounds like burning!
  • I did that. (Score:5, Interesting)

    by digitalsushi ( 137809 ) * <slashdot@digitalsushi.com> on Thursday June 17, 2004 @09:16AM (#9452139) Journal
    I've been doing exactly this same thing for a while. I found that it got extrememly obnoxious, so I dumbed mine down to just play a wave file whenever I get pinged by someone pinging me from a command line ping. I don't know why the length is different than the crap pings that come in every 8 or 9 seconds, but with this swatch definition below, it seems to trigger only when I am pinged by hand.

    So, put this in your swatch file that watches your firewall log:

    watchfor /firewall-ping.*LEN=84/
    exec "/usr/local/site/bin/ping-wave.sh ping.wav"

    That script just locks the darned thing so it doesnt pop and crack if i get pinged twice:

    ping-wave.sh:
    if `grep OPEN /etc/pingwatch.lock 1>/dev/null`
    then (echo -n > /etc/pingwatch.lock) && (/usr/bin/play /usr/local/site/etc/soun
    ds/$1) && (echo OPEN > /etc/pingwatch.lock)
    fi

    And here's a link to my ping wave for you to use:

    ping .wav [digitalsushi.com]

    I also used the naturalvoices [att.com] website to make a nerdy computer lady announcing new entries in my arp table. You can grab wave file [digitalsushi.com] too if you want. Here's the script I have for that:

    put this in your /etc/crontab or whatever:

    0-59 * * * * root /usr/local/site/bin/arp-watch

    and then make the above command contain this:

    #!/bin/bash

    for each in `arp -n |grep -v "Address"|grep -v "eth0"|awk '{print $3}'`
    do
    if grep $each /etc/arptable 1>/dev/null
    then :
    else /usr/bin/play /usr/local/site/etc/sounds/new.arp.entry.wav && echo $each >> /etc/arptable
    fi
    done

    if anyone can improve upon my bash, please, i have no ego. :D
    • Re:I did that. (Score:5, Interesting)

      by AndroidCat ( 229562 ) on Thursday June 17, 2004 @10:01AM (#9452648) Homepage
      I was curious about all the Sasser mutants and such trying to hit my port 445, so I whipped up a program to open the port and see if they were trying to say anything. (Boring, they want my end to say something first.) I used the text-to-speech to have it say "Poink!" when it opened the port and "Splat!" when it closed. When a few hit at the same time, it's "Poink! Poink! Poink! Splat! Splat! Splat!". Almost as entertaining as having a few beers out back listening to the bug-zapper. (It would be better if my end sent a buffer-overflow to crash attempted attacks, but too much work.)
  • IDS (Score:4, Interesting)

    by Aliencow ( 653119 ) on Thursday June 17, 2004 @09:16AM (#9452140) Homepage Journal
    I'd rather have a silent firewall... I'm not the kind of people who likes having a big warning everytime some script kiddy scans my port 31337 or pings me... hell ZoneAlarm will warn you if there's a DHCP server on your network... and people who don't know better think that OMG IT'S A HAX!!!!!!11111111...

    Maybe it could be nice on an IDS system though..
    • Re:IDS (Score:3, Funny)

      by pjt33 ( 739471 )
      IDS being silent seems more appropriate. After all, even he acknowledged that he was "the quiet man".

      Waits to be modded down Offtopic by non-Brits.

  • by bludstone ( 103539 ) on Thursday June 17, 2004 @09:16AM (#9452142)
    Grrr.. ch ch ch.. grrrr. ch ch ch... grrrr.. ch ch ch..

    I need to replace the harddrive soon or im going to be without a firewall.
  • by FerretFrottage ( 714136 ) on Thursday June 17, 2004 @09:16AM (#9452144)
    "Ding Dong"..."No one's home"
    "Ding Dong"..."Not interested"
    "Ding Dong"..."Go away"
    "Ding Dong"..."Leave me alone"
    "Ding Dong"..."porn you say? well come right on in"
  • by lukewarmfusion ( 726141 ) on Thursday June 17, 2004 @09:16AM (#9452146) Homepage Journal
    It sounds like the screams of thousands of users, as I hit that red button marked: Power.
  • by CCIEwannabe ( 538547 ) on Thursday June 17, 2004 @09:17AM (#9452153) Homepage
    I use windows, so my firewall sounds something like this

    Holy Crap! Help me lord! Bleeep!
  • A rock smashing glass
    Yay metaphors!
  • Do you (Score:5, Funny)

    by BCW2 ( 168187 ) on Thursday June 17, 2004 @09:18AM (#9452164) Journal
    ever get the feeling that some people have entirely too much time on their hands?
  • by trance29 ( 614645 )
    I can just imagine a war movie (your network) with bullets (bad packets) ping'n off of armor (firewall).
  • by Apocalypse111 ( 597674 ) on Thursday June 17, 2004 @09:19AM (#9452176) Journal
    Microsoft firewall: "Please don't hurt me! Hey, you look cool, can't possibly be malicious, come right in... OW, OH, THE PAIN!"

    Norton firewall: "Bahahahaa! You can't get past me! I AM INVINCIBLE!!! *fires the firewall equivilent of fully automatic weapons into the air*"
  • by evil-osm ( 203438 ) on Thursday June 17, 2004 @09:19AM (#9452183)
    Like a 486 on its last legs, fans barely moving, and the smell of cooking dust.... ahhhh.
  • Depending on how much of that blotter paper you've licked, it may sound like the colors that taste like music.
  • by cHiphead ( 17854 ) on Thursday June 17, 2004 @09:23AM (#9452226)
    how long until full fps style interaction with firewalls? this is the beginning of a Shadowrun-like matrix net where audio and visual become a big part of hacking
  • Mac Version (Score:2, Informative)

    by inertia187 ( 156602 ) *
    Here's the mac version:
    #!/bin/sh
    tail --follow=name /var/log/system.log | \
    awk '
    $0 ~ /DROP/ {
    system("open /Library/Sounds/Submarine.aiff");
    }
    '
    Don't forget to run it as root.
    • Re:Mac Version (Score:5, Informative)

      by hackstraw ( 262471 ) * on Thursday June 17, 2004 @09:58AM (#9452623)
      Unless you installed GNU tail, the OSX tail does not have the --follow option.

      Don't forget to run it as root.

      You don't need root access, you only need to be in the admin group, which I would guess you already are if you have root access.

      Plus, I would guess that the default option for playing an aiff file is via Quicktime, which may get intrusive.

      Lesson learned, don't mod something as informative unless you know what it says.
  • by Shoten ( 260439 ) on Thursday June 17, 2004 @09:23AM (#9452234)
    "AAAAAAAAAAAAAAAAAIIIIIEEEE! Too many hits!!!! F*#%ING Slashdot!"

  • by Saint Aardvark ( 159009 ) * on Thursday June 17, 2004 @09:24AM (#9452248) Homepage Journal
    You know when you've got popcorn going and it gets to that crazy insane stage when things just go nuts? That's my firewall these days.

    I send firewall logs to DShield.org, and you should to. The firewall is set to only log 100 denied packets at a time, so lazy bastard that I am I set a cronjob to reset the counters every hour. That was a few months ago.

    Last week I happened to be looking at the logfiles, and I noticed something: an hour was no longer enough. The counter hits 100 within 10 or 15 minutes. I can watch the hits come in, and it's all Windows crap: Port 445. Port 137. Port 139. Port 1026. That's it. Nothing interesting -- you know, no stealthy scans by l33t cr5X0rZ, no probing for open relays, nothing.

    Two thoughts before I go:

    First, this makes for excellent demonstration material. A coworker mentioned that he was considering moving from Windows to Linux because he was tired of all the viruses and worms. I showed him what tail -f on my firewall logs looked like, pointed out that it was all Windows junk, and he was convinced. Gave him a Knoppix CD and made another notch on my belt. :-)

    Second, I'm lucky: my ISP has not yet started firewalling ports yet. A friend's ISP just started, and now his web and mail server, which I'm doing DNS for, are no longer available from outside -- they've started blocking those along with 445, 137, 139, and so on. Sadly, it looks like the ISP has no provision for lifting this if you can prove you're l33t enough, so it looks like he's screwed.

    Honestly, though, I'm not surprised. Yeah, it sucks that the Internet is no longer open -- but it sucks that the Internet is no longer friendly, too, and the one is a consequence of the other. As much as I bitch about Windows and Microsoft, I don't think they're entirely to blame...you get that many people joining something, and you're going to have enough asshats to ruin it pretty quickly.

    • I agree completely about the amount of windows junk out there. On the network at uni, there is a known issue where the Linksys wireless-B router will just give up an die after about 5 minutes of exposure, do to all of the junk flying about. The joy of several thousand mostly unprotected Windows machines with uneducated users ...
  • by Faust7 ( 314817 ) on Thursday June 17, 2004 @09:25AM (#9452259) Homepage
    ...but I imagine the Linux Gazette web server sounds like Rice Krispies about now.
  • Already done... (Score:5, Informative)

    by Cheerio Boy ( 82178 ) on Thursday June 17, 2004 @09:26AM (#9452273) Homepage Journal
    Can't read the article due to 'slashing but it's already been done by peep - the network analyzer:

    http://www.usenix.org/publications/library/proce edings/lisa2000/gilfix/gilfix_html/
  • by mikael ( 484 ) on Thursday June 17, 2004 @09:32AM (#9452344)
    For me, the sound of something bouncing off the iris of a stargate from SG-1, is the most reassuring noise I could imagine hearing if I converted IP traffic to sound.
  • by enrico_suave ( 179651 ) on Thursday June 17, 2004 @09:32AM (#9452351) Homepage
    'Ecky- ecky- ecky- ecky- pikang- zoop- boing- goodem- zoo- owli- zhiv'

    =)

    e.

  • I know windows XP is supposed to have a firewall, but for the life of me I can't find it.

    Maybe now if I listen closely.....
  • Peep [auralizer.com] is a great tool to hear what's going on out there... where the hackers play !

    It plays sound whenever an connection is made on a designated port (smtp, domain (DNS), http...) but also can play specific sounds based on events (keywords on log file -> snort, auth.log etc.)

  • Now I can write a virus that before it kills your NT systems, it plays Beethoven's "Ode to Joy" with this little tool. Or perhaps it plays Queen's "Another one bites the dust". Or, I can make it quasi-speech-synthesize something...
    "all your base are belong to us", anyone?
  • by SadPenguin ( 776485 ) on Thursday June 17, 2004 @09:49AM (#9452513) Homepage
    PEEP the Network Auralizer [sourceforge.net] This project, cooperatively developed by a faculty member and student in the Tufts University Comp. Sci. dept. answers this question. PEEP applies sounds to network events. Its really cool, i had checked it out, but didn't have much time to get very far with it. I imagine this software's authors will appreciate it if you give it a gander, and let them know.
  • ...hundreds of Jaffah slamming into my Stargate's titanium iris as that god-damned Code-Red and related worms STILL hit my web server every day.

    Will nothing cure my ails short of packet-sniffing at the ISP level to determine who is infected and cut them off?
    • ...hundreds of Jaffah slamming into my Stargate's titanium iris as that god-damned Code-Red and related worms STILL hit my web server every day.

      No shit. YTF is Code Red *still* out there, filling my error logs. Maroons. . .
  • by JessLeah ( 625838 ) on Thursday June 17, 2004 @09:52AM (#9452542)
    o/~ Badger badger badger badger badger badger badger badger badger badger badger badger MUSHROOM MUSHROOM! o/~

    o/~ Ohhh, a worrrm, oh noooo it's a worrrrrm o/~
  • I was thinking it'd be cool to set up your SMTP server so that each piece of detected and rejected spam would make it play a successive phrase of the SPAM Song.

    Spam...
    Spam...
    Spam...
    Spam...
    Lovely Spam!...
    etc.
    • I used to have the computer bing on new email.
      Then it could talk and tell me I have email.
      In the end it was Monte Python's "spam spam spam" yelling at me with any new email. One day, while walking in, the computer started to scream at full volume and scared the hell out of the wife.

      Now the PowerMate just silently pulses. :)

      PS: my average rejection time is once every 15-20 seconds with a new inbound (not rejected yet) hitting every 2-3 minutes and 1-2 actually getting past all spam filters and showing up i
  • I don't know what a firewall sounds like, but I think I hear a web server screaming...
  • by Darth_brooks ( 180756 ) <clipper377@g[ ]l.com ['mai' in gap]> on Thursday June 17, 2004 @09:59AM (#9452633) Homepage
    My firewall sounds like a really bad techno song. It starts with a nice driving rythem with hits on 137 that come out like:

    bump-bump-bump-bump-bump-bump-bump-bump-bump

    Then maybe a few attempts at an SQL worm on 1433-1434 so i get the second layer of the track; that's sound like 'dittlit-bump' so the track now becomes

    bump-bump-bump-dittlit-bump-dittlit-bump

    Now we've got some rythem going, but we there's always that annoying yet musical sound that comes interrupts the song the first time you hear it, but then you get used to it. We'll call that a portscan. ports 135-137-445-3127-5000

    dah-dah-dahdah-dah-dah-dahdahdah

    But at just that moment I get a fresh IP from my DSL provider, and the last guy who had it was running eDonkey, AIM file transfers, and bittorrent (as happened to my a couple days ago) and all the crap clients for said programs don't realize the old client died, so they keep trying said addresses.....we'll call that a big-ass bass hit that starts the loop over again.

    BOOOOOOOOOOOOOM-BOOOOOOOOOOOOOM-BOOOOOOOOOOOOOOO M

    Holy crap, my firewall sounds exactly like the Strong Bad techno song, minus the 'the system is down' quote. (ahhh the benfits of coyote linux. or IPcop.)

    http://www.homestarrunner.com/sbemail.html
  • ... you know, my firewall sounds just like John Cage's 4'33"! This is sooo weird!
    -m
  • by kbahey ( 102895 ) on Thursday June 17, 2004 @10:21AM (#9452851) Homepage

    I guess they are now wondering what a Slashdotting [wikipedia.org] sounds like?

    Anyone wants to guess?

  • Walking many ports over many hosts creates a lawnmower effect. A single IP port scan creates a stripe.

    What I want to see is when a machine on the inside or a DMZ has a port open to it, say port 80 & 443 - I want to see when somebody who JUST walked my net with a lawnmower then starts sending ADDITIONAL packets to the open ports. Maybe you could do that with sound. The code could take a src-ip that just mowed you, and assign a sound to it. Then, any additional data to open ports would create a sound, m
  • by Gary Destruction ( 683101 ) * on Thursday June 17, 2004 @10:32AM (#9452950) Journal
    DOS attack -- Hail storm, Pong or Arkanoid with gold bricks
    Firewall penetration -- Breakout or Arkanoid with lasers
    Block All Traffic -- Mario with a star
  • I've been running a firewall with 'audio feedback' for quite a while now. Back then I wanted a filtering bridge, and the simplest way to do it was to scrounge a PC, some SMC network cards, and download the free version of KarlBridge which could do this. One of the tricks used in this software was to use the 'sound' connector on old PC motherboards (from when they could only make beeping noises) to drive an 'activity' LED instead of that speaker. Unfortunately, the computer I choose for this had a little sp
  • They should get the wave file from Unreal Tournament where the announcer says "DENIED!" whenever a packet drops.
  • Then you'll remember the scene that could fit what a firewall sounds like: No! No! No! No! No! No! No! No! No! No!
  • With a bit of awk or grep, you could have your snort logs give you sounds for different events. Sure, it's not interesting to hear every single worm hit your firewall, but whenever someone's doing sneaky scans etc it would be a good idea if a big speaker went BONG in the war room.
  • Interesting concept (Score:3, Interesting)

    by LightlyToasted ( 95756 ) on Thursday June 17, 2004 @11:23AM (#9453415) Homepage

    I seem to remember a similar concept being used in fighter aircraft. The pilot would hear certain directional sounds to indicate inbound missiles. The advantage of using sound over a visual display was that the human mind is apparently very good a detecting the direction where a sound is coming from, and it avoids overloading the visual display further.

    I've also heard of using sound in the monitoring systems for mechanical equipment. Operational events are assigned a certain sound, and a "normal" state of the equipment would have certain patterns and frequencies that an operator would recognize as normal. The operator doesn't have to know what each individual sound means. If something abnormal happens, the operator get a "sense" that something is wrong by the change in tempo / frequency, etc.

    If done properly, I think that adding sound feedback to a network / firewall monitoring application could be useful.

    • by feargal ( 99776 )
      Compared individually, eyesight is actually better on its own at determining directions and vectors than our aural senses. The limitation of sight of course is that it only works for our field of vision; one presumes though that these days pilots don't scan the skies for bogies, they use consoles/HUDs instead.

      When you combine visual and audio cues together however you get the greatest response from the user. If a pilot with good situational awareness momentarily focuses on another display while the missle
  • Totally useless (Score:4, Interesting)

    by Rayder ( 39469 ) on Thursday June 17, 2004 @11:28AM (#9453453)
    What you need to ear is not the DROPed packets, but the ACCEPTed ones.

    If you make a diferent sound for every port/address/whatever packet you receive it becomes easy to recognice when the traffic is anormal.
  • My Firewall only ever makes this sound: *arf* *arf* *arf*

    But that could be because my dog is named Firewall.
  • What he/you are looking for is this project [freshmeat.net].

    (the website is a bit down right now so it seems, see google, you know the drill)

    It's been on slashdot before...
  • but I can't bring myself to do so, knowing that they have tried to screw [slashdot.org] over the REAL Linux Gazette [linuxgazette.net].

    Sorry, but I just can't support SSC.

  • Worth a try (Score:3, Interesting)

    by orangepeel ( 114557 ) on Thursday June 17, 2004 @12:56PM (#9454485)
    Years ago I worked as part of the helpdesk service at my college. One of our public labs had a large line-impact printer.

    [I'll include a side note for those who do not know what a line-impact printer is. Do you remember dot-matrix printers? No? Ok, no help for you. But for those of you who do remember them, you probably realized how having a single print-head that had to travel back and forth across the page contributed to their relatively slow printing speed. No doubt some of you came to the same conclusion the developer of the line-impact printer did: instead of having a tiny print head move back and forth across the page, simply create a huge print head (well, very wide but not very high) that could print an entire line at a time. That makes for a faster printer, and also a much more reliable printer (far fewer moving parts). Hence you can still find them in industrial applications where people need large volumes of low quality prints. This also happened to be ideal in an 1980's computer lab visited by uber geeks who needed to print out their code, and psychology students who needed to dump pounds and pounds of statistical data to a printer somehow. Anyway...]

    The helpdesk office at this particular computer lab was attached to the lab with the line printer. So it was close enough you could hear it running. With normal, plain text like you'd see in a printout from a computer program, the printer (being an impact printer) made a recognizable sound. Mostly a wavering, roaring sound. However, when some idiot decided to dump a PostScript file to the printer - and with the printer just being designed for plain text (i.e. no freakin' PostScript like all the signs said) - the sound would change to a solid, angry roar as each entire page would be filled up by PostScript code. The difference in sound proved to be incredibly useful. Anyone sitting in the helpdesk office, even if they were concentrating on some other task and thus seemingly oblivious to the faint sound of the printer, would somehow hear the change in the sound. They'd know that someone had screwed up and that they needed to go and stop the job before the printer blew through an entire box of fan-fold paper.

    As I say, we'd just tune into the change in the sound automatically. It wasn't even an especially conscious thing. You'd be working away on some task, completely engrossed in homework or something, and all of a sudden your brain would tune into the fact that the background sound had changed. With normal printing it was completely tuned out. You never noticed it until there was a problem. How fantastic is that? This is a great feature of the human brain - you can be giving your full attention to one task, but some other part of your brain is still somehow listening out for changes in your environment and will let you know if something's changed. I would find this so useful for a firewall. The sounds would have to be low volume and carefully chosen so as not to drive me insane in either instance (normal operation or "uh oh" mode), but I'd really love to give this a try.

    It's such a coincidence ... I was at work this morning and something just like my original printer story happened. We've got large format DesignJet printers from HP (basically giant InkJet printers that can handle 3 to 5 foot wide, 300 foot long rolls of paper). When they print, they run a vacuum fan to hold the paper down and steady while the print head zips back and forth across the sheet. The vacuum fans produce a dull sort of roar while printing. BUT, there's this second sound while they're printing ... the sound of the print-head zipping back and forth, back and forth, across the sheet. Well, this morning, I was dealing with some stuff that really had me focusing on the task at hand. All of a sudden, some part of my brain alerted me to the fact that I'd been hearing the dull roar of the vacuum fan for a while, but not the sound of the print-head moving back and forth. This is really an am

If mathematically you end up with the wrong answer, try multiplying by the page number.

Working...