I usually kill the gas mileage in the integra on the back roads... Amazing what a 5 spd can do for your sanity
That being said, before the 5 spd, I also would go kill the gas mileage in the bonneville on the back roads. windows down, sunroof open, and curvy roads. never drove too fast, but just enough to get a feel for the roads.
I also hit golf balls. A bucket of balls at a driving range, or across the river at the run down apartment building can do wonders as well.