One of my current favorites (pun intended) is the use of little
Micro generators powered by water and gravity; the turbine spins
around hoving just above the bottom of a water vortex created by
a circle... - with more than enough room for fishies to go under
and around it safely. I forget what it's called but it's the
kind of thing you could build in a weekend with some concrete...
and a giant turbine hooked up to a generator... Maybe eough to
power a house. Cool stuff.
