I don’t normally do this, three days in a row discussing the same topic, but I keep running across more information.  According to this article on ZDNet News, Motorola yesterday announced “that they have successfully demonstrated a methane gas-powered fuel cell, which can provide enough juice between chargings for a month of cell phone calls.”  The thing is the size of a laptop battery (4″ x 6″ x 1/2 “).  Yes, methane.  No, we don’t need any more fart jokes.  NEC and Sony are working on similar devices.  NEC expects to have a salable product sometime in the next two to four years.  Motorola and Sony have not announced their plans.

Apparently, somebody is working on the “power shoes” idea.  According to this article on Discovery News, a company called SRI International is working on lacing a boot with electroactive polymers to convert the mechanical energy of walking into electric power.  The Defense Advanced Research Projects Agency (DARPA) is one of the project’s primary sponsors.

Finally, on a somewhat related note, the 2001 World Human Powered Speed Challenge is being held this week in Battle Mountain, Nevada.  The vehicles used in this race resemble bicycles only in that they have two wheels and are human powered.  The world record for a single rider over the 200 meter course is 72.75 MPH, set last year by Sam Whittingham.  You get a “flying start,” which means you’re already up to speed when you cross the starting line.  You can see information on last year’s event (including some cool pictures of the vehicles) here. Some people are projecting a record of 100 MPH in the not-too-distant future.  That’s faster than I’m willing to drive my car!