Another example of 'junkbot'-type robot: http://www.instructables.com/id/Simple-Bots-Wobbler/
Simple Bots: Wobbler: "Simple Bots: Wobbler by randofo
Typically, you learn how to wobble before you learn how to walk. But in the world of bots, anything is possible! That is why a day after showing you how to walk and two after showing you how I roll, I am back to show you how to do a little wobble wobble. That's right! In almost no time, you can be out wobbling around with the best of 'em. All of the parts in this project are simple to find and even less-than-experienced bot builders should be able to make this one pretty easily. And, more experienced bot builders should be able to have some fun modding this one, as the casing leaves a lot of room for experimentation.
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