Twirling Battery Provides Instant Energy for a Dead Cellphone(inhabitat.com)
inhabitat.com
Twirling Battery Provides Instant Energy for a Dead Cellphone
http://www.inhabitat.com/2010/01/06/twirling-battery-provides-instant-fix-for-dead-battery/
3 comments
It would probably be more effective to twirl the phone too. Easier, less space taken by the ring. You just need a system that makes sure you won't drop the phone by mistake.
Cute, but twirling is not really the best way to harvest energy from a human. Even if your goal is a really really small generator.
Somehow this leads me to imagine pull-cord powered phones.