Some researchers at the University of Michigan are clearly misdirected in their goals to harvest energy from a knee brace. The device generates electricity in a method similar to regenerative breaking in a hybrid
car, so the attempt is to harvest wasted kinetic energy in your knee from when your leg hits the ground and at other points in your stride. Hopes are to reclaim this energy for use to power gadgetry on your person, or perhaps a prosthetic limb, and the researchers claim it only takes an extra watt of metabolic power for each watt of electricity generated -- compared to 6.4 watts of metabolic for a hand-crank
, for instance -- but we'd say that's still one watt too many: if we were meant to use our own calories to power devices, why did God make batteries and solar panels?