Inventor: Hero (busy man)

　　Date: First century A.D.

　　How it works: A person puts a coin in a slot at the top of a box. The coin hits a metal lever, like a balance beam. On the other end of the beam is a string tied to a plug that stops a container of liquid. As the beam tilts from the weight of the coin, the string lifts the plug and dispenses the desired drink until the coin drops off the beam.

　　Proof of complexity: Early modern vending machines actually used a similar system, before electrical machines took over.

　　Quirk: It was devised to distribute Holy Water at temples, because "people were taking more Holy Water than they were paying for," Humphrey says.