This is a demo of the Funx capacitor, a Glitchy analog synth designed by Zippy:

It’s controlled by three mercury tilt-switches and of course, buttons-and-knobs. Fun to play! The sound changes as you rotate the thing. It’s brain is seven square-wave oscillators: three for the “notes,” three for the blinky lights, and one for the “tremolo” mod. The whole thing mounts on a round, blank circuit board and fits inside this acrylic rocks-glass I got at Lucky’s!!!! 1/4″ output also installed to crank-it-up and annoy the neighbors.

via Prankster Dice