An anonymous reader writes "Volkswagen just unveiled a new car at the Qatar Motor Show that gets an astounding 100km for less than a liter of diesel fuel – that's the equivalent of 313 miles per gallon! The XL1 concept car is an upgraded version of the VW L1 vehicle, and it features an ultra-efficient diesel engine in addition to an electric motor that is powered by a lithium-ion battery. The vehicle is currently slated to enter production in 2013 and is expected to cost approximately $29,500." Autoblog calls it 261 mpg, which isn't too shabby, either. At less than a thousand pounds empty, I hope this comes with a really good bike lock.