Just like one of the horrible truth at the heart of the Matrix – that humans are terrific energy producers – Max Donelan of Vancouver's Simon Fraser University has developed an 'energy harvester' that looks like an orthopaedic knee-brace. When the person wearing the device walks, the knee's motion drives gears that turn a small generator, and because it can be engaged only when the knee decelerates the forward motion, it may actually help in making walking easier while generating 5W of power. In this way, it can power appliances and devices and even battery rechargers.

Here's The Economist article which describes several applications in developing markets where institutional energy is not readily available.

Personal applications.

The most effective exercise regime that I've ever had was when we lived in Ottawa. There, I rode a mountain bike (with big knobby tires) to the office and back. It was a 21 km cycle down bike paths and took an hour each way. My office had a shower too, so I could clean up nicely for the day. I loved it because once I got on the bike (which was mostly a matter of routine), I had to go to the office. And, once I got there only stealing the bike (yes, they cut the chain from the bike storage rack in the back of the parking lot if you can imagine) would stop me. Moving to Dallas meant that riding a bike to work was dangerous given the heat and the traffic.

Other routines were less rigid. I tried running, but soon realized that I could reduce the time it took by turning left instead of right at that point, and eventually that I wouldn't get sweaty if I didn't leave the house…

So, lately my wife has been suggesting that I should ride a stationary bike in front of the TV. My problem with that model is that I won't get the same level of 'have to do' commitment once I get on the bike as I did with the mountain bike, unless….

… my cycling powers the TV, just as Gilligan powered the appliances on Gilligan's Island. Now, that would be a great exercise regime, wouldn't it? Is there such a device like this? 

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