Here’s a first: someone built a 500-pound potato battery to power his sound system. The potatoes — each generating 0.5 volts and 0.2 milliamperes — were put into groups and then connected inside of a truck.

“In this case the potato provides phosphoric acid, which enables a chemical reaction causing electrons flow from copper to zinc. The zinc came from galvanized nails and copper came from small pieces of copper.”

[Lattier via MAKE]