Human Being as source of electricity

Self-inspired by my previous post, I am posting one more post on electricity generation. In the present day human beings are used as a source of electricity indirectly i.e. by using the physical energy of the human. Simplest example is the dynamo in the bicycle. We also know that scientists have found out a way to use heat energy from human body in small amounts. We all know that brain communicates through nervous system with the help of bio electric signals. My idea is to convert these signals to suitable form such that we can use it re-charge the mobile phone,mp3 player..etc or to use as source of power for an LED torch. It might be difficult since the source is very weak and supply is not regular. But, no-one can predict its purely impossible. Most important thing is that care should be taken so that it should not disturb the actual job which the neural signal does. An alternative I suggest is that we can develop an artificial system after thoroughly studying the chemical and electrical properties f the neural signals so that the system can generate power in larger quantities.