go out yonder, peace in the valley
come downtown, have to rumble in the alley
oh, you don't know the shape I'm in-- the band
This is an intriguing search engine being developed by Princeton. You draw something and it attempts to match it with images from the Internet or from specialized libraries. Expected to be quite useful for engineers and the like.
(It's getting a lot of traffic and it's pretty slow. You might not want to bother looking at it unless you have a broadband connection.)