Hack yourself – self knowlege through numbers
"The Quantified Self is a collaboration of users and tool makers who share an interest in self knowledge through self-tracking. We exchange information about our personal projects, the tools we use, tips we've gleaned, lessons we've learned. We blog, meet face to face, and collaborate online."
This site gives that warm feeling of finding friends in a warm café after a long chilly November walk. There are great videos from the show-and-tells on Vimeo.
Eyetracker on the cheap
"Behold the latest ocular assault weapon from the Graffiti Research Lab, openFrameworks, The Fat Lab and The Ebeling Group: The EyeWriter. It is a low-cost eye-tracking apparatus + custom software that allows graffiti writers and artists with paralysis resulting from Amyotrophic lateral sclerosis to draw using only their eyes....This instruction set details how to make your own solderless eyetracker for only $50 dollars using a hacked PS3 Eye and a cheap pair of sunglasses."
http://www.instructables.com/id/The-EyeWriter/