So I finished putting together the random music box. It sounds awesome. It's based on a PIC microcontroller and randomly generates music based on traditional chord progressions. There are a total of 5 square waveforms, 3 for the chords, 1 for the melody and 1 for the bass. I need to sort a few things out with the source code and add the potentiometers to level out the chorus/melody/bass. I used a digital camera so the audio/video stinks, but you get the picture.
Credit to Kevin Weekly for the original schematic/code/awesome idea.