「 What's behind my shadow. 10/15/2008 10:26:00 PM 」
Moving your limbs meaning you have to move your muslces, and you need to have nerves to react along with it. If you'd lost your arm by amputation or other means, what would a replacement be like?
A mechanical arm, with high technology that will connect the system to your nerves, and it acts on hydraulics to allow smooth movement and lesser effort to move it? But you'd have to replace it everytime you grow, if you're growing, and send it for maintanence. What if there was really such a replacement, how much would it cost..
The same goes for legs, you'd have to clean it, frequently grease it, and people would build weapons with it.