Johnny Chung Lee out of Carnegie Mellon University has discovered some features of the Wiimote and developed pertaining software that can further enhance user interactivity. One of them personally being my favorite of the three, allows a user to multi-touch interact with his/her desktop when projected onto practically any surface. And here's the kicker; this can be done at a MUCH more affordable price (not including the price of a projector if you don't already have one) when compared to the more expensive products of Microsoft's Surface and Apple's Multi-Touch products. His other projects Wiimote projects can be found here.