From the Supertou.ch Black Lab, we use a kinect to control a 3D avatar in a 3D rendered environment. We recognize when we are near certain physical objects in the room as well. Then we switch to our Coverflow app utilizing the iPad as a show controller.
Once in Coverflow we control media via hand gestures. Music, presentations, movies and more can be controlled.
The closer you get to the system, the lower the volume, the father away you get, the louder it gets. The system also responds to height data and adjusts the view accordingly.
Much thanks goes out to @_ChrisRojas_ and @alpaykasal for the long hours.