Aside from the obvious choice, there's vehicles scooting around on bioethanol, batteries, fuel cells, and all sorts of other alternatives, but a recent breakthrough in Kansas City, Missouri has opened up the possibility of using natural gas. Currently, the cheaper and cleaner burning methane isn't feasible in modern vehicles due to the extremely high pressure (3,600 psi) and gargantuous tanks required to actually use it. Researchers at the University of Missouri-Columbia and Midwest Research Institute in Kansas City have devised a way to change all that, however, by using corncob waste to create "carbon briquettes with complex nanopores capable of storing natural gas at an unprecedented density of 180 times their own volume and at one seventh the pressure of conventional natural gas tanks." In layman's terms, this discovery allows natural gas to be held under much less pressure and in thin-walled tanks similar to cells used on current vehicles, which could instantly make natural gas a viable (and readily available) alternative fuel source. A prototype system has been working just fine since last October, and the backers are currently crafting a second revision in hopes of storing even more natural gas and driving production costs down, but there's still no hard deets on when this invention could see commercial light.