YouTube via kizel4 "The Auduino, a DIY synthesizer, originally developed by the tinker.it team.
I decided to make a few modifications to the original. I added a switch that enables a light dependent resistor (LDR) to control the rate of the noise, which essentially means the more light that hits the resistor, the faster the tempo.
I also did not want to commit to one mapping of the Auduino -- I liked both the the smooth frequency and the stepped pentatonic mapping, so I added a switch to move between the two synthesiser parameters.