What's your best mpg, non-hybrid?
 

In your non-hybrid cars, what has been the best mpg you've been able to achieve?
Recently I took a highway trip through New York state with my '91 Oldsmobile Ciera and on the way from southern CT to Victor, NY it got 42 mpg. I'd seen it do well previously, but was never able to get an accurate measurement. This time I was able to calculate it, and was surprised how well it did.
I am pretty sure some of the advice on how to get good mileage here on this forum helped, so thanks to all of you for that. I don't drive as aggressively as I may have in the past. I've also read that the stretch from Syracuse to Buffalo is relatively flat; it was used in testing rail locomotives for high speeds in the past. Maybe that helped too. But it makes me wonder why some of these older model cars are capable of doing so well, yet the latest models of similarly-sized cars only seem to be getting 30 mpg highway? Not much progress over the years I guess.