I retired 3 years ago, and started slowing down. On long (400 miles each way) drives to my mom's in SoCal, I used to average 26 mpg going 72 mph. When I slowed down to 62 mph, my mileage climbed to 32-34 mpg. Going even slower (55 mph), I got 36-38 mpg. This is in my 2002 Nissan Sentra SE-R Spec V 6MT (originally EPA rated 22/28 mpg with a combined 24 mpg estimated mileage).
Last summer I got serious. I volunteered in some national parks in Utah, New Mexico, and Colorado, and I logged my gas tanks with the $4/gallon gas. Since then, I'm averaging 37.5 mpg over the past 9000 miles, 155% of the original EPA estimates.
This Spring I bought a used 2006 Scion xB 5MT. It has an original 30/33 mpg EPA rating, with 31 mpg estimated combined mileage. I'm getting 46.5 mpg on this car in the 1500 miles I've owned it (150% of the original EPA combined mileage).
Looking forward to meeting you folks, especially any north Bay Area folks, and exchanging ideas.