Yorart

University of Tokyo and Sony Computer Science Laboratories developped a belt that electrically stimulates the muscles in the forearm that move your fingers. 

A belt, which contains 28 electrode pads, can take control of your hand and teach you how to play an instrument.  

To aid the controlling of finger movement, PossessedHand, a device with a forearm belt that can teach when and which fingers should be moved. PossessedHand controls the user’s fingers by applying electrical stimulus to the muscles around the forearm. Each muscle is stimulated via 28 electrode pads. Muscles at different depths in the forearm can be se- lected for simulation by varying the stimulation level. PossessedHand can automatically calibrate the system for individuals. The automatic calibration system estimates rela- tions between each electrode pad, stimulation level and mus- cle movement. Experiments show that PossessedHand can control the motion of 16 joints in the hand.

Completere article here and video.