Last we heard, Canon had patented fuel cell technology that could use one fuel cell to power all of the various functions of a camera, no matter their required current. Canon's latest, more in-depth patent goes along with this first idea but takes the principle to the next level-one fuel cell will power the entire camera and all of its attached accessories, like a hotshoe flash. With the one battery/fuel cell philosophy, Canon promises "simplification of the electronic equipment system and improvement of power generation efficiency thereof." So it all sounds great, other than that "how much will these fuel cells actually cost" part of the equation and the "are they really better than rechargeable batteries?" issue. [patent via photographybay]