Scientists are working on a clever way to utilize the evaporation powers in nature for energy generation. Have you ever seen the mysteriously pretty sight of a lake in winter covered by a layer of thick fog? When the cold winter air lies over a warm body of water like a lake, the water molecules evaporate from the surface water into the colder air above it. A lab at Columbia University in New York recently created two devices that generate electricity from this evaporation process, by making use of the change in humidity. The first device is a floating, piston-driven engine that generates electricity causing a light to flash, and the second a rotary engine that drives a miniature car. The researchers were successful in getting the car to roll on its own, solely powered by evaporation.