Linux Journal has an article, written by a high school teacher, on the bots built in his class. The current bot runs on Gentoo Linux and has some clever features, such as wheel encoding using computer mice. Now using parts from mice to build bots is nothing new, even using them to create encoders has been done, but this design bolts a largely-intact optical mouse to a drive wheel — it even uses the freakin’ mousepad as the encoder wheel!
I also like the parking sign seen in the background of one of the pics: Linux User Parking Only.
Thanks, Alberto!