Honda today rolled out a new zero-emission, hydrogen fuel cell car, but you and I won't be driving one anytime soon. The 'FCX Clarity,' which runs on hydrogen and electricity, emits only water and none of the noxious fumes believed to induce global warming. It is also two times more energy efficient than a gas-electric hybrid and three times that of a standard gasoline-powered car, the company says. The problem? A lack of hydrogen fuel stations. Here's the story.