I would buy some old tape recorders and a bike with a dynamo. The bike can be used to drive the tape recorder, the dynamo generates power to amplify your sound. The faster you bike, the higher the pitch ;) An extended version would include an accu/battery system --- Sjaak http://www.livelooping.be/ http://euroloopfest.com/sjaak/ http://www.myspace.com/sjaakovergaauw