A bristle bot is a simple vibrabot. It is made by putting an offset motor onto a toothbrush head. Then you put a battery on it and it will start to move. Some people change it a little bit. Like using a computer chip or kitchen scrubber instead of a toothbrush head. Some people make them RC.
I played some with the concept(s) at some point, one afternoon - but it is in a pile of to-do's now ;/
I made a pretty terrible bristlebot a while ago and made an instructable about it.
Note: I made this before I learned about porgramming, or anything
there it is...
I really like this one because it answers a question of mine: can you "steer" a vibrobot?