Both cleanly powered and built from two recycled bicycles, scrap steel and wood, leaking water jug and a lacrosse stick, this pedal powered tennis ball launcher is a unique and simple invention. Basically, the person riding the bike powers two other bike wheels which act as a launcher. A hand operated lever drops tennis balls into the mechanism at will. Take a look at the inventor’s site for more information and a slow motion video.
See also our post on Alternative Energy – Bike Generators.