Overflowing water pools with barriers operated by level or flow in some other pool would be the intuitive candidate. Very close to popular mental models of elec

Overflowing water pools with barriers operated by level or flow in some other pool would be the intuitive candidate. Very close to popular mental models of electricity and people do like to have fountains around. Fountain/playground intermediates seem to be particularly popular. It's been baffling me since late childhood that this isn't a thing everybody loved until they became "oh no, not another one of those!" frequent. Remember when fountains of that giant stone sphere slightly elevated by water pressure type weren't definitely not cool anymore yet?