| Starvin Marvin was born in the same period I created the Cosmic Space Beeper. It has 2 oscillators with a low frequency connected to 2 oscillators which have a high (audio range) frequency. All oscillators have a potentiometer for speed control and the high frequency oscillators can also be controlled by a LDR. The low frequency oscillators can be turned off with a switch and they have a LED that flashes at the oscillator speed.
It also has a starve pot. (hence the name Starvin Marvin*) which lowers the frequency of all the oscillators, so it's kind of a pitch control, but it also makes all the oscillators somehow effect each other. Basically it just makes the whole thing act weird, which of course is just what I wanted.
I found the schematic of the filter on a forum and I've build it before as a stand-alone unit (whackyFilter). Later I discovered that it's actually part of the Weird Sound Generator by Music from OuterSpace which looks a lot like Starvin Marvin but with more controls, so I'm definitely gonna build that one someday.
*The name 'Starvin Marvin' belongs to a SouthPark character that I used for the front design. Name and image are used without permission but I don't think Trey & Matt will mind ;)