Whilst the use of knee braces have long been used to either support or prevent damage to the ligaments of American Pro footballers, recent scientific developments have highlighted a much more intriguing use: the knee brace harnessing the kinetic energy of the knee movement and storing it. Boffins from the University of Pittsburgh and the Simon Fraser University in Canada have found a way to harness 30 minutes cell phone time from 1 minute's walking. Keep that up and The Pittsburgh Steelers could power their own floodlights during matches!

It has to be said that such a notion is actually along way off, but so far the bionic knee brace is causing quite a stir. It appears as a conventional example of a supportive knee brace; it weighs 3.5 pounds (that's 1.6 kilos for the more metrically minded). It harvests the same energy from the muscular breaking motion of the knee in walking as regenerative vehicles, such as the Toyota Prius, will harvest electricity from the breaking capacity within the car. A minute or so of walking at a moderate pace of 2.2 miles per hour generated 5 watts of power.

This is not a new idea: aside from knee braces such energy harvesters have been tried in backpacks and heels of shoes. Unfortunately these devices have either been much heavier than the knee brace, or have simply been less effective in providing enough wattage.

The benefits of this knee brace technology have been outlined by the researchers: they envisage it use by the military, supplying the energy for everything to GPS devices to night-vision goggles. The energy from these knee braces will also help those people in areas where the mass generation of electricity is not possible: as with clockwork radios, these devices might allow the use of low-powered computers. Medically Knee Brace power could be used to help those who require prosthetics or exo-skeletons.

Of course, the idea of the human as battery has been the stuff of cinematic nightmares for years. Despite the beneficial claims, there will probably be a nagging doubt in everyone's mind. There may be visions perhaps, of armies of "Cybermen" clunking around the planet, controlling the population through the power of their energy-harvesting knee braces. The growing pace of technology, has always fed these more negative speculations, but hey, at least this form of knee brace fuel is a greener type of conquest!