Mgestyk's gesture-based interface technology turns the wax-on flick of a wrist into a rotation, the wave of the hands into a scroll and a thumbs up into a press of the Enter key. It's all done with a 3D camera that translates hand movements into commands for any computer application, regardless of the lighting. And if the promotional video is to be believed, it does it very, very well.
I tend to be cynical about motion interfaces: the metaphor of pushing an arrow key or waving a mouse simply seems more straight forward and less elaborate than doing a pantomime routine in front of my computer all day. That said, I find the apparent integration of Mgestyk's technology terribly neat: even if I don't particularly have any interest in doing all my computering this way, I could easily see a future iteration of the Wii going this route and be fine with it.