Yep... There was one group of independant people that got something ridiculous (I want to say like 500 mpg or something) by just not braking and not accelerating. To stop? They drove around the block a hundred times until it eventually came to a stop.
LOL, well, I can believe that. I've rented cars in the past that have a little trip computer that tells you (in somewhat real time) what mileage you're getting. When coasting, it would peak at 99. Under decent acceleration, it would drop into the single digits.