Today, after a nearly two-year tease, General Motors unveiled the final design for the car that it hopes will save the company: the 2011 Chevrolet Volt, the world's first production plug-in hybrid. The Volt is designed to drive 40 miles on a single charge of its giant lithium-ion battery; after that, an onboard 1.4-liter four-cylinder flex-fuel engine kicks in to power the electric motors that drive the car. GM will most likely make 10,000 of the cars in the first year of production; it's expected to go on sale in November 2010. It's unclear how much the car will cost, though the relatively unproven lithium-ion batteries could drive the cost close to $40,000. Government incentives could help drive that cost down closer to the $30,000 mark.