Click above for more pics of the Dough Heffron's 75 mpg "tandem" Metro Like a number of other folks who didn't get much attention at the time, Doug Heffron was worried about gas mileage and pump costs way back in 1993. That was back when this particular blogger had a VW Jetta that could be filled to the tippy top for $11, and having to spend $13 was considered criminal banditry. But Doug wasn't happy with merely cheap fill-ups and 56 mpg in his Geo Metro Xfi. So he turned it into the car you see above.That meant installing tandem seating on the left side, fairing the wheels, changing the gearing, and chopping off the right side and replacing it with, well, nothing but a wing. Once finished, the car got 75 pg. All that work might sound like a lot for an extra 19 mph, but one should expect a bit of aero tweaking and math to squeeze a 34-percent gain in fuel economy from an already frugal econobox.The car was driven for two years in all four New England seasons, and then gas prices went down and it was put away in a barn. In 2006, however, the barn doors opened again, but Doug hasn't said what he plans to do with the car. We're not saying that everyone should drive this type of... thing, but if a guy in his garage can crank out something like this, then... come on Chevy Volt ! Thanks for the tip, Ted!