By taking an Arduino microcontroller and adding two RC filters the cpu can control the LittleBits Korg Synth (http://littlebits.cc/) components. Add a PS/2 compatible mouse and you have a fun instrument. More at http://moddersandrockers.com/littlebi….
Sound demos start at http://youtu.be/rvLWifnFIUs?t=7m4s
The mouse with its two axis of control and three buttons allows for a fun interface. This version is the first that has the note bending feature. I will be adding an opto isolator so the controller can read MIDI data. This will allow me to play the LittleBits Synth kit using MIDI.
At the moment I have not trimmed the CV scaling to give correct note spacing but it is close enough for this demo.