It's not just the fitness club types in Hong Kong attempting to generate a bit of renewable energy, inventor Lucien Gambarota -- the very man responsible for converting all that cardio into voltage -- is showing off some micro-wind turbines for even more power bill relief. There's currently only a single wind turbine on a small outer island providing energy to Hong Kong, the rest of the city just doesn't get enough wind for traditional turbines to do any good. Not so with Gambarota's new micro-turbines, which can generate electricity with as little as 2 mph of wind, and keep turning at all times from the slightest of breezes. The little windmills are actually gearwheels, mounted in a array. They can be arranged in different shapes and sizes, from two to thousands of square meters. The energy is put into a battery, which then powers appliances in the building. Currently the micro-turbines go for about $25 for a set of 20 gearwheels, but that price should drop considerably once they begin to be mass produced.