DIY projects typically aren't best known for their miniaturization efforts. But this synth, it's really small. It was built by Mixtela, who has a whole blog full of tiny projects — many of them MIDI-related. But this small synth is his most small. It takes MIDI signals over USB and turns them into noise, and all the necessary processing to do that is inside the USB connector. It's about as pleasant to listen to as one of those musical greeting cards. But it's really small, remember.