When my algebra students were first introduced to Heron's (or Hero's) formula, I always told them a brief historical note about his invention of a steam-jet propelled automaton (called the æolipyle) that he created during the first century of the common era. It was just a novelty experiment and didn't do a lot, but let's put it in some historical perspective. Once Hero's aeolipyle was forgotten, we don't know of any other person inventing a steam engine until the Ottoman inventor and all-around genius Taqi al-Din in 1577 - and he was considered the greatest scientist on Earth by his contemporaries.
Over Christmas I received the little "Book of Secrets" as a gift and learned as I leafed through it that he was also the inventor of the first known vending machine. Apparently in ancient times folks were required to pay for holy water to wash themselves before entering the temples, but it seems they didn't always cough up the cash..... so... Heron invented a device to help keep them honest.
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.
According to Erik Davis's book "Techgnosis: Myth, Magic & Mysticism In The Age Of Information", Heron actually designed robots to perform entire plays. They would move about the stage, enter and exit on their own, and
Another staged a Dionysian mystery rite with Apollonian precision: Flames lept, thunder crashed, and miniature female Bacchantes whirled madly around the wine god on a pulley-driven turntable.And just so you fully experienced the drama, it was complete with sound effects. Here is the machine he used to produce the effect of thunder. the Yeah, I would be lined up to see that show myself.