An mp3 player (would probably have to be solid-state storage for power concerns) that has a kinetic battery charger built in. As the user walks the inertial energy is transfered to a generator and then to a storage device. While the power requirements would probably make it difficult for this to completely power the device, It could act as a way to improve the play time on a single charge of the original battery.-- photojunkie, Jan 20 2005 Solar powered MP3 player http://www.treehugg...solar_powered_m.phpSolar powered MP3 player (one of many) [csea, Jul 07 2007] Shakable MP3 Player http://www.nytimes....7dcf7ef3396&ei=5070Shake the MP3 Player to change tracks [csea, Jul 07 2007] Human Powered MP3 Player Research http://campus.io.tu...f97/doc/kuipers.pdfCranking seems best [csea, Jul 07 2007] They use kinetic capture mechanisms in watches all the time, so it should not be that heavy...-- photojunkie, Jan 20 2005 True, but as photojunkie says, this would extend battery life rather than replace the battery.-- david_scothern, Jan 20 2005 Or in the heels of your shoes. Or piezoelectric blah blah blah . . . .-- contracts, Jan 20 2005 I was thinking of exactly the same thing yesterday, in work I have my mp3 player on a cord round my neck and I noticed it was swinging when I was walking round the warehouse. I thought it would be so good if this thing had a kinetic charger in it then it could be charging the battery whilst I'm walking, and with it being MP3 it doesn't use much more electric than a digital watch does, a solar powered MP3 player would probably also work fine.-- darrenforster99, Jul 07 2007 That Sandisk "Shaker" isn't shake-powered. It has a battery in it--the shaking controls the song mix.-- baconbrain, Jul 07 2007 [baconbrain],
Ah! Right your are. I should have read a bit more:
"After all, the idea of shaking something to mix up the contents — in this case a music playlist — is something even a baby can understand."
Link title corrected. Also came across a study that seems to say that shaking isn't an ideal power source for an MP3 player; they favor cranking. [link]-- csea, Jul 07 2007 Should be quite bakeable, especially for flash-ram units as they use very little power. Hard-drives are a bit more power hungry.-- wagster, Jul 07 2007 random, halfbakery