The Virtual Reality Synthesiser was my final project for Computing in secondary school (at Advanced Higher level). It features a subtractive synthesiser you can control by waving your hands in the air (kind of like a Theremin), along with a fully featured drum machine and audio recording/playback system.
If you have an Oculus headset, you can download a demo here and try it out. You can also try the demo on SteamVR headsets via ReVive.