Greatest instruments you've never heard of

Buggering hell, I've gone post crazy. And it's another video, but trust me, this one is even better than the last one.

Ever heard of a Theremin? Probably not, but then most people haven't. In case you haven't, it's an instrument that was invented in the early 20th century and is played by moving your hands through a shaped electro-magnetic field. By all accounts they're bastard hard to play so that makes this even more astonishing. And yes, the chap who appears to be wafting his hands about over a Corby trouser press with a TV aerial attached is indeed playing the vocal part. There should be more Theremins in modern music.