As long as your toothbrush is sitting around unused and unloved, you might as well put it to good use with this DIY Bristlebot courtesy of the folks at Evil Mad Scientist Laboratories. All you need is a brush with angled bristles, a pager motor and a watch battery. Minutes of fun and tooth decay will be your reward. To see the Bristelbot in action, and learn how to build one yourself, hit the video after the jump.
@jawzxy: I think the only way this could hurt a cat would be if he'd swallow the thing !
p.s. I can't believe they felt the need to make a laborious instructional video. One look at a photo of the thing should be enough information to allow anyone with an IQ over room temp to build one. It's hardly the most complex machine ever conceived.