Even those of us who don't have pools can appreciate the Ecolight, the pool light that's a microcosm of a hydroelectric plant. This design concept is super-easy to use — mount it on the water jet from the filter pump, and the flow spins its tiny turbine just enough to light up the ring of LEDs within.

Best of all, the electricians don't need to get involved, because you just pop this sucker onto that water pipe in the pool. It's completely self-contained, lighting up as long as the pump is on. Hydroelectric power? Great idea! Or you could save even more money by not having a pool at all.

Via Yanko Design