This research group use projection (it seems like?) to make a guitar hero for the piano. Basically Guitar Hero-like notes come flying towards keys on the piano.

It's nifty. Could maybe make learning for beginners fun and more of a game. Doesn't cover that much ground in terms of learning piano, but hey I'm all for making piano more fun.

Working on Beethoven's Appassionata Sonata, Mvt 3.