RX8 writes "Canon, Inc., has taken the wraps off prototype rechargeable hydrogen fuel cells, the likes of which may one day power digital cameras, media players, and printers. Canon's demonstrated fuel cells win even more points on the environmental front: while companies such as Toshiba, Sanyo, and NEC have also been working on fuel cells (and had been expected to have developed fuel cell-driven notebook computers by now), those efforts are based on DMFC technology which derives hydrogen from methanol, producing small amounts of carbon dioxide (itself a greenhouse gas) in the process. Canon's cells obtain hydrogen from a refillable cartridge with no toxic byproducts."
Computers are unreliable, but humans are even more unreliable.
Any system which depends on human reliability is unreliable.