It may look a bit like a sea mammal out of water but the Volkswagen XL1 concept car is going to make it to the production line. No one thought it would. And it will be the most efficient production car anywhere, the company says. Volkswagen’s Formula XL1 Concept is a plug-in hybrid, meaning that it’s capable of running on battery power alone for awhile, and then if you need the extra range, it’s got a tiny two cylinder diesel engine that can extend its range. Reportedly, it gets a staggering 260 miles per gallon. Volkswagen says that it will be producing about a hundred XL1s, to be made available first in Germany and later in the U.S.