Princeton University engineers seem to have developed the technology to harness energy through rubber, which will eventually allow things like your shoes or your pants to charge your new or refurbished cell phones.
A lot of what I read about the technology went over my head, but the gist of it is that ceramic nanoribbons will be inserted into silicone rubber sheets, which will be used to make shoes, clothes, etc., and the ribbons, when bent by actions like walking and breathing, harness energy. Apparently, these ribbons are really efficient and can harness about 80% of mechanical energy and turn it into electrical energy.
Besides the fact that it would be really cool to be able to charge your phone by taking a bike ride, the technology will prove extremely valuable to people with internal instruments like pacemakers. No longer will these people need to undergo surgeries just to have the batteries on their devices changed because the devices will be constantly charged through daily activities.