One way is to fix some piezo-electric material on the soles of a pair of shoes so, as its wearer walks, the soles press down on the material to produce electricity.
Enough current can be generated to run gadgets such as radio players and watches.
The research is nearly complete. Making commercial products is the likely next step.
The electricity created can even be used for transferring data from one person to another via the skin. The human body thus becomes another device, together with mobile phones and digital entertainment gadgets like MP3 players, in what is called a personal area network (PAN). A handshake would allow an automatic exchange of business cards electronically between the PDAs of both persons.
From Straits Time.