Interestingly enough, I have a game on my Nintendo DSi that seems to be similar to the Microsoft Kinect in that it uses the system camera to track the user's head movements. The game (Looksley's Lineup) shows a lot of promise in that you actually can "look" inside the frame of the device screeen and try to spot things hidden behind other things and around corners, etc.



The drawbacks are that the system is very picky - you have to have be in good light and have a solid, contrasting background behind you for the system to work well. To be fair, it's only using a single camera and the Microsoft device appears to have more than one, which might help with triangulation.
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