RoboBotics
B.E.A.M

Biology-basicly how well you do the .E.A.M
Electronics-the brains of your  robot
Asthetics-this is how nice it looks
Mechanics- the body of your robot. 

B.E.A.M is an analog based technology used in the construction of inexpensive robots that require no programing, and can be more complex than some programable that can be made for more money
Schematics
H-switch
Edge detectors

Outside links
how stuff works is good
Solarbotics BEAM homepage
another good one
Telus
Beam-online a very good site

Coming soon
Electronics