Environmentalists would have you believe that leaving the faucet running while you brush your teeth puts an unnecessary drain on the environment. We always disagreed, and if Jin Woo Han's concept Mini Hydro Turbine ever goes into production we might finally have something to back up our argument. The device would capture the "free" energy of your tap to spin a little generator, in theory producing enough juice to charge up an electric toothbrush or shaver. That actually sounds somewhat reasonable, but Han's suggestion of powering your boiler with this thing is probably a bit optimistic. It would also take an quite optimist