Microsoft's Surface multi-touch table sure is cool, but who has $10,000 to spend on a gadget like that? I personally have maybe fifty bucks to my name right now, so I guess I'll have to fulfill my multi-touch itch with a cardboard box and a webcam like this guy.

Seth Sandler, an undergraduate student at UC San Diego, built a portable multi-touch pad out of a cardboard box, a piece of glass, paper, and his Philips SPC900NC webcam. The camera picks up on the shadows created by your fingers when they're placed on the pad's surface. A tracking software then transfers the motions onto a computer screen. Multi-touch goodness at an incredibly low cost—looks like I can afford to eat this month after all! [New Scientist]