The Kinect gaming peripheral has been out for the Xbox 360 since late last year - however, it seems the most interesting things that people have been using it for are largely non-game related.
One of the uses hackers have discovered for it? Using the Kinect as a motion capture device! The motion data can even be saved in Autodesk's Motionbuilder, making it possible to port the animation over to Maya, Max and XSI.
There's a ton of videos on youtube regarding this, but here's a few to get you started. It's apparent that there are some issues with depth accuracy, occlusion and jiggles in the capture - but I'm fairly certain those things will be sorted out soon.