I have yet to attempt at getting the thing tuned, but by runing the PWM output of the Fading sketch (a steady ramp up and down from 1 to 255) i was able to verify that it does indeed control my rather excentric synth. Thoughts, suggestions and critics welcome.
NOTE: The capacitor in the lowpass filter at the bottom is 470 uF, apologies for not adding the value.

Arduino Control Voltage by Dana Simmons is licensed under a Creative Commons Attribution-Share Alike 3.0 United States License.
Based on a work at code.google.com.