Probably no one here will like our family's cars:
2001 BMW M5
1971 (I believe that's the year) Olds Cutlass Supreme
1999 GMC Sierra
I am 15, so legally I have never driven
but when my father drives, especially in the M5, when on the highway, he will speed up to 85-90, then neutral (idles at around 750-800rpm) and coast down to 65 or so and repeat, when getting off the highway, he just puts it in neutral and coasts the whole way down the highway/exit ramp, he almost never stops for red lights because he never gets one, our town has horribly timed lights; there is one every maybe 750 feet, and if you drive as many have told me "Eco-friendly" you stop for about 80% of them...how eco-friendly are you? My father will just floor it and make it through them all, obviously worse mpg than normal driving, but better than waiting. When starting off, he just releases the clutch which is not only better for your mpg, but also your clutch. On average he gets 20-22 mpg in his car, but most get around 16...or less. Original brakes and original clutch while most get about 60-80 thousand miles, he is at 130 thousand still going good.
The pickup, and the olds are both automatic, and rarely used, so not much is done in them.
Btw, just to see what you CAN get in the worst conditions (mpg wise) in the M5, he hit full throttle and I reset the computer to see minimum mpg. That was...4 then 5 then 6, then it was time to stop the acceleration so he let off the throttle.
I plan to get a 1975 citicar and some 1995-2003ish BMW 3 or 5 series as my cars. Lol sorry guys, the fun is too much appeal to get a great mpg car...