Here are two different implementations of “Theremin Hero”, after the popular Guitar Hero video game.
Thereminhero.com has some info, but for details on implementation, check out the comments in the YouTube video. [hat tip Hackaday]
Next, Cornell University’s ECE 4760 course publishes student final projects on the web– consistently a rich source for ideas. D.L. and S.J. present a Theremin Hero project, including source code.