Back in 2009, the Obama administration said the U.S. needs to reduce exhaust emissions from cars, trucks, minivans, and everything in between. Simultaneously, those vehicles need to provide better fuel economy, as measured by Corporate Average Fuel Economy, otherwise known as CAFE, which are administered through the federal National Highway Traffic Safety Administration. After wrangling back and forth with the automakers and their supporters, the government explained its finding, provided numbers, and more or less said, "Go forth and meet these. And if you don't, here are the consequences."So what does this mean to you, the average car buyer? The number most bandied by the press is 54.5 mpg. This is the figure most automakers' entire car and truck lineup must average by 2025 to be in compliance with the government regulations. Not always explained is that CAFE is not the same thing as the numbers we see on the window stickers of new cars, and in advertisements. Those are provided by the Environmental Protection Agency, and are typically about 20 percent lower than CAFE numbers, according to the NHTSA; our own calculations showed the EPA combined figure between 20 and 30 percent less than the official CAFE numbers. It's complicated further by the fact that the CAFE number involves the vehicle's "footprint," that is, its overall size. The breakdown works something like this: compact car (e.g. Honda Fit); midsized (Ford Fusion); full-sized (Chrysler 300); small SUV (Ford Escape); midsized crossover (Nissan Murano); and large pickup truck (Chevrolet Silverado). Doing the math, that ranges from an EPA combined 23 mpg for full-size pickups, up to 48 mpg for subcompacts.All of which got us to thinking: do any vehicles on sale today meet the 2025 standard? Yup; pretty much any electric vehicle meets it today, for example. But EVs haven't exactly caught the public's imagination -- and pocketbooks -- the way manufacturers had hoped, and besides, putting an EV on a list of fuel-efficient cars is sort of cheating. Still, we managed to find seven vehicles that meet the future standard today that aren't just affordable, but are even fun and interesting to drive. Absent from the list: Full-size trucks. None currently meet the standard, but there's hope for the future. Rumors have swirled that diesel engines could make their way to the half-ton segment, and if they do, they're sure to drive fuel economy numbers significantly higher than they are now.