Skittle-based beat sequencer, a tangible and edible music interface. This is a prototype developed over the course of two evenings, with a webcam and Processing.
The webcam is mounted using cardboard/wood above the screen, and Skittles are placed on the screen -- a cheap responsive surface (when a circle is active, it turns green).
Future directions may include: more sensor types (e.g., a slider for tempo control), note-sequencing mode, and assigning the different colors to different rhythms or instruments (purple as bassline, or yellow as "every other measure").
There is a cut in the middle where it transitions from solo improvisation to three people interacting simultaneously. Any out-of-sync audio/video is due to my frazzled camera.
One of the other big problems: people like to eat Skittles.