The new Fiesta is here:
http://consumerguideauto.howstuffworks.com/2010-ford-fiesta.htm
If this car runs a 125-140 horsepower engine coupled to a five speed manual not only should it exceed 40+ m.p.g. but could get you a serious speeding ticket too.
I currently drive a Ford ZX2 (Escort) :



I added the Bomz Racing Short Ram Intake, a Pace Setter catalytic converter back exhaust, MSD High Output Coil Pack, Massive Speed 8mm Superconductor Plug Wires and Autolite Iridium XP spark plugs. I also run Mobile 1 full synthetic 15,000 mile oil and change just the oil filter every 3,000 miles. Full oil change at 15,000 miles.
This car is quick, every bit as fast as my 1964 Mustang H.O. 289 4v, and gets 31-37 m.p.g. depending on how “hard” I drive her. Went from 130 horsepower to over 140 horsepower too.
In it’s original configuration the car was still very quick and they handle great. The modifications were done only because I wanted to do them except for the exhaust. I had a leaking exhaust pipe and figured if I had to spend over $300 for a o.e.m. exhaust I would put out the $260 for the better high performance exhaust. Let that engine breathe and boosted torque as well as an increase in m.p.g. The only thing I wish it had was the standard 5 speed transmission.
There are plenty of the Escort ZX2 and 3rd-4th generation Escorts out there that won’t break the bank, will save you on insurance and are miserly on gas. The ZX2 uses a bit more gas, normally 31-35 m.p.g. vs. 35-40 m.p.g. of the standard escort, but has enough power to get you both out of and into trouble. Oh, those mileage figures are in a 50/50 mix of city/highway driving.
Well, there are plenty of these cars out there to be had along with the Chevrolet Cavalier, Chevrolet Cobalt, Dodge Neon, Ford Focus, Toyota Priest, Mazda Protege and etc… Don’t let miles in excess of 100,000 put you off either. These are all based on Japanese or German chassis/drive-train. As long as they have been maintained you can get 200,000-300,000 easily out of them. I paid $5,500 for my ZX2 with 66,000 miles on it and I love it.