Even better than a theremin? I'm pleased to see another musical instrument/device that is played without having to actually touch it.
"The team [Rensselaer Polytechnic Institute's student Zane Van Dusen, along with Pauline Oliveros, a world-renowned musician and distinguished professor of the arts at Rensselaer] designed and implemented a computer interface that tracks the movement of a user’s head to allow them to produce electronic sounds and compose music on a virtual keyboard in both solo and ensemble settings."
This is just the beginning. They hope to use this interface for a variety of tasks.
"Beyond musical communication, Van Dusen sees potential for the device to allow users to create verbal exchanges: “The interface could be adapted to create speech software, allowing those who suffer from CP to form full sentences, rather than just yes or no responses.”"http://www.sciencedaily.com/releases/2007/05/070513074258.htm