Believe it or not, Volkswagen is already at work developing its next-generation Golf, due to arrive in 2019. When you're dealing with one of your best-selling models, it's good to start things early. Apparently, VW has a goal of making the Mk8 Golf one of the most economical mainstream cars ever made. So how do you go about doing that? You apply technology and lessons learned from the XL1, which manages 261 mpg. Now, VW obviously can't apply all of the XL1's high-tech to an economy car.

Remember, the XL1 costs $146,000. What VW engineers can do is take advantage of many of the XL1's aerodynamic solutions. But this creates a bit of a problem: because the Golf is a hatchback and a short car overall, it won't be able to utilize all of the long and low XL1's aerodynamic efficiency. One possible solution, according to a VW source in a conversation with Autocar, "could be to extend the hatchback's rear spoiler further over the rear window, along with deep blade-like extensions along the upright sides of the window." VW will also have to come up with additional weight saving methods, possibly with greater use of carbon fiber. Fortunately, they've got plenty of time to figure all of this out.