Electric Shirt

It does not produce as much energy as the knee brace but it is light. Using nano technology scientists have made a shirt that can produce electricity.

"The fiber-based nanogenerator would be a simple and economical way to harvest energy from the physical movement," Zhong Lin Wang of the Georgia Institute of Technology, who led the study, said in a statement.

The nanogenerator takes advantage of the semiconductive properties of zinc oxide nanowires -- tiny wires 1,000 times smaller than the width of a human hair -- embedded into the fabric. The wires are formed into pairs of microscopic brush-like structures, shaped like a baby-bottle brush.

One of the fibers in each pair is coated with gold and serves as an electrode. As the bristles brush together through a person's body movement, the wires convert the mechanical motion into electricity.