If anyone has ever heard of them, it is a competition of two or more robots trying to push each other out of a ring. You can buy kits to construct them, and it is pretty cool.
My particular kit uses infrared lasers to chase the other robot. It has two lasers, placed like a humans eyes in the front of the robot. When both lasers make contact, the robot moves forward, when one laser makes contact, it turns to that side until both lasers make contact again.
It also uses a contrast detecting laser positioned on the bottom, aiming at the floor. The ring is black with a white outline, hence the contrast. When the laser acknowledges the contrast, the robot turns around and drives away from the line.
The object of the match is to push the other bot out of the ring, but you have no control over your bot aside from what you program it to do.
You must program it, but I don't have a clue how to program the motor to function.
If anyone knows how to program a motor, please tell me how. D:
I just thought it is a cool way for people to start with mechanics, and an interesting thing to try.
The Systm Episode (Where I learned all this crap from):
http://revision3.com/systm/sumobots