Sure, Kinect is cool. There’s definitely something to be said for waving your hands at a TV and actually accomplishing something. That said, the tech can still be kind of awkward and janky, and on top of that, gesture recognition systems and their cameras tend to be expensive, especially considering the general lack of fine tuning across the board. Microsoft is working on another system that might be able to solve the price problems. SoundWave works much like Kinect, but will work by using your computer’s built-in microphone and speakers, and nothing else.
The trick is the Doppler effect. For those of you who don’t remember your physics very well, the Doppler effect has to do with the way a frequency of a sound changes depending on how far away you are from it. The perfect example is how the sound of a police siren seems to morph has the police car flies by you. You can probably see where this is going.