I saw this on the news the other day, a moving speed hump (up & down) to generate electricity to power street lights.
Imagine this in the dark/wet/ any time at all.
http://news.bbc.co.uk/1/hi/england/somerset/4535408.stm Having visited their website
http://www.hughesresearch.co.uk/index.htm and looked at the video the idea of this being put to use scares the living **** out of me