Many people have watched and been amazed by the Kitchen Music video, which shows music seeming to be triggered by kitchen items.
“Unfortunately, it’s fake!” note the guys at Shiverware. “Before we found out, we set about for 6 hours making our own version, which really works!”
The video demonstrates how you can use an Arduino board and capacitive sensing to turn ordinary stuff into MIDI controllers.
There’s information on capacitive sensing available at Arduino Playground.