Continuing today's theme of weird shit people are doing with TouchOSC, Gregory W Brown has an Electromagnetically Prepared Piano that he plays exclusively from his iPad! Using a combination of microphones to create feedback loops, Gregory is vibrating the strings on his piano with electromagnetic fields; without touching the keys!
"The piano is sounded by means of the rapidly varying magnetic field created by audio signal passing through electromagnets in close proximity to the strings. The oscillations in the magnetic field alternately pull and release the strings, causing them to vibrate, creating sound. This process allows the piano to be played without touching the keys or strings."
The demo video starts off with this very slow ambient-space-thing, but at around 4:00 in it becomes an ambient chainsaw!