In the past, I have sometimes left a "thankyou" comment, but I am wondering which of the "share" buttons which are usually associated with such an article would also be useful. I wouldn't use facebook, because it's not of interest to most of my friends, and even those who might be interested at sometime are unlikely to want to see it right now.
It would also be good to use a system which keeps track of my recommendations, for my own future reference.
I've never used the other net sharing sites (digg, reddit, etc.), so, before looking into them to find which, if any, is appropriate, I'm asking the Slashdot community.