I recently thought about using capillary action to power a generator (capillary action lifts water, right?) then researched it and learned that 1) I'm not the first one to think of it and 2) it wouldn't work anyways. Then I thought, why can't you use a vacuum to lift the water through a tube, like siphoning gas (though maybe I'm just missing something, and siphoning doesn't actually work or something). Any ideas? Could you use a vacuum to siphon water up a tube, let it fall and turn a generator?