Build a pulse sensor

Nice build with IR to figure out your pulse.  The video is pretty good and it looks like a simple build with an AVR (arduino) to translate the signal.  It could be a little cheaper by using non-radio shack parts, but overall the build is pretty cheap.

http://makezine.com/projects/ir-pulse-sensor/?utm_source=feedburner&utm_medium=%24%7Bfeed%7D&utm_campaign=Feed%3A+%24%7Bmakezineonline%7D+%28%24%7BMAKE%7D%29&utm_content=%24%7BGoogleReader%7D