Pavegen Systems has a nicely packaged retrofit system for existing pavements that will harness the power of pedestrian footfalls. Seems like it could be used on city sidewalks as well as in malls, stadiums or other highly trafficked indoor spaces.

Each paver has the capacity to power 20 lights similar to the one that is embedded in the paver. 5% of the power harnessed is used on the integrated light, the purpose of which seems to be to make it clear that power is being harnessed. The other 95% of the power can be stored and used to power nearby information displays, new media art work, storefronts, etc.

seen via the guardian