You could wait for Microsoft's Surface tabletop touchscreen computer to drop in price so you can put one in your living room. Or you could build your own, like the guys at Maximum PC did. Helpful fellows, they documented the whole process step by step so you can do it yourself.
They used off-the-shelf parts, a PS3 Eye camera, a small form-factor desktop PC, and a mix of open-source software and other readily available apps to run the whole thing. The video, below, is pretty impressive. It shows, however, that the value of Microsoft's product is in the quality of its finish rather than the concept itself.

