Hydrogen is lightweight and efficient as a fuel. When it burns, you get water as the exhaust, and the fuel cell technology that burns the gas is well developed. The major hang-up has been how to produce hydrogen without needing lots of fossil-derived energy.
Apparently, the way to cheap hydrogen is through aluminum. Purdue researchers earlier this year announced they'd found a way to use aluminum to get hydrogen from water. Today a Chinese ceramicist who did graduate work in Portugal says there's an even simpler way to derive hydrogen. This process uses powdered aluminum at room temperature, under normal atmospheric pressure. This use of modified aluminum powder could promise a cheap way to produce hydrogen for fuel cells.
It's long been engineers' hope to power everything from portable devices to cars with power cells. We have video of experimental hydrogen-powered cars here.