This, my friends, is a theremin:[youtube http://www.youtube.com/watch?v=pSzTPGlNa5U]
A musician friend of mine shared this with me with the following explanation:
so the theremin is an instrument that you play without any physical contact, it has to do with where you place your hands in relationship to the instrument. in this vid her left hand controls volume and right hand controls pitch (her hand shakes for vibrato)
Translation: the theremin is magic.