This was in a series of robots I made when I was really fond of the idea that instead of giving a robot wheels with traction, it should just be "something" that could push itself around on free roling wheels.
Hard to explain, but take a look at this:
It is tha base of an old Nielfisk Vaakum Cleaner.
Wouldn't it be fun to have a robot placed on top, with arms that it could push itself around with? (whatch video to catch my drift)
I want to do more of that kind some day soon ;)
I mainly show you this because of the video; I hung up a camera behind my head, and a remote in my hand to start it every now and then - just as an experiment, I would love to see other peoples ways of building, filmed that way :) (I know I am a mess, btw)