The Bleep Labs Robo Audio Synths from ThinkGeek is essentially “an awesome, little, light-controlled, analog synthesizer” — includes .25″ output jack for external devices (amps, etc.). Video after the break.
The photocell talks to the main oscillator and (with a little more technical stuff that we just won’t get into here), you get bilps and bleeps of pure electronic wonderment.
[via ThinkGeek]