This is awesome: Middle-school and high-school kids from Manhattan built their own instruments and amplifiers as part of their art program. There's a short radio show hosted by student "DJ Kev" featuring their work. As Music Thing said, where was this when I was 14?
Along similar thematic lines, have you seen Konono No1? They play Congolese trance music through a homemade sound system, including hand-carved microphones and electric thumb pianos. It's... interesting.