Neither is likely to go on sale soon. Panasonic doesn't have any firm plans for commercialization but said it hopes to have them on the market by the end of 2012.

A handful of big-name consumer electronics companies have been developing DMFCs for the last several years, but are yet to bring the products to market. For the last few years most companies have vaguely stated "next year" as a commercialization date but it's an answer that's given no matter when asked.

That might be about to change. Toshiba recently made the clearest promise yet to DMFC commercialization: sometime during its current financial year, which ends in March 2009. At the recent Ceatec show in Japan the company demonstrated a working cell phone that included a DMFC, but Toshiba isn't letting on yet if this will be its first product.