http://www.smith.edu/hsc/museum/ancient_inventions/hsc18b.htm
Now that's just downright cool!
Designed by the Greek inventor Heron, this coin-operated holy water dispenser was used in Egyptian temples to dispense water for ritual washings. Worshippers would place a coin into the machine and receive holy water to bathe themselves with before entering the temple. At the end of the day, the slot machine would be emptied of its coins and refilled with holy water for the next day's worshippers. Dropping a coin into the slot machine initiates a chain reaction: the weight of the coin depresses a metal pan, which in turn results in the opening of a valve, which in turn allows the water to flow out for the worshipper.
