Drum Lights
I connected an Adafruit Trinket microcontroller to a piezo vibration sensor. This sensor is capable of detecting the vibrations of a drum head, which is then used to control a ring of LEDs. I haven't published the code online, simply because the project really doesn't involve a lot of code. Thank you to my friends David and Jacob for demonstrating the device, since I'm woefully bad at playing snare drum!