Titanium should save weight on construction, and you can run the battery pack as the thigh or even the lower leg, depending on heat issues. I don't think the first gen cyberlimbs would be as large as a regular one - I mean thinner, less flesh and such for muscles and fat insulation. The battery would replace that bulk and could conceivably 'sleep' when the leg isn't being used, such as when you're seated at a desk. A 12-hour battery would be fine, though a 10-hour may save some size. Length of time charging would also be an issue.

Umm, why not use some ideas from Nikola Tesla and simply build in ambient power accumulators that recharge the batteries (or simply power the limb directly) from the amount of energy that is being broadcast into the environment? Especially in the age of the Wireless world.

Besides it not working?

I recall Mythbusters attempting something like this and it required 150 feet of stretched out wire to get about the equivalent of a watch battery.

It does work, but it certainly doesn't provide enough power for something like cybernetic limbs. There was a 100' string of LED christmas lights on the wall outside my bedroom a couple years back that kept glowing very faintly even while unplugged, just drawing off of the EMI generated by all my electronics.

Right, it does work, but only if you have a long spread out wire. You had 100' (likely more because I think a string of LED lights goes both ways with the wire) and had enough power to maybe fully power an LED or two. So yes, it works but it isn't something that could be applied usefully to something like this.

I suppose I shouldn't have said 'doesn't work'. It just isn't useful.

You... haven't been getting any headaches while in that room, have you?

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