Slatterz writes: Logitech has introduced new mice that use two lasers rather than one to work on a variety of previously unusable surfaces. The first laser picks out imperfections in the surface of a tabletop while the second laser focuses on microscopic imperfections highlighted and uses those to direct the cursor. The technique, dubbed dark field microscopy, allows mice to be used on almost any surface, including glass as long as it is more than 4mm thick. Link to Original Source
The rule on staying alive as a forecaster is to give 'em a number or
give 'em a date, but never give 'em both at once.
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