2009 Volkswagen L1 Concept

What's good gas mileage? 30 mpg? 40 mpg? The 50-mpg combined rating of the 2011 Toyota Prius, the most fuel-efficient car sold in the U.S. this year? Nah. How about 261 miles per gallon? Or, for the Europeans in the house, a mere 24 grams of carbon dioxide per kilometer. You heard right. The Volkswagen XL1 plug-in hybrid concept shown here, being launched at the Quatar Motor Show this week, achieves a fuel efficiency of 0.9 liters per 100 km, which for North Americans translates to a bit more than 260 mpg. Designed to build It's the third iteration of VW's "1-Litre Car" project, which has now...