Your Car Sucks! Fuel That Is. How To Save Gas

The best way to save gas is to not drive at all. The options to not drive your car are simply not available to many people thanks to the wisdom of American city planners and suburban sprawl beyond the bus and rail lines. You can drive less by carpooling though. May cities have websites where you can post your location and look for others to participate. Then you can haul butt in the HOV lane legally.
To save a few tenths of a mile per gallon read the itty bitty print on the side of your tires. Typical car tires often take between 32 and 35 PSI. You can get a gauge of 99 cents at Wally Mart and a compressor that you plug in the cigarette lighter plug for about 10 bucks. Air is cheap, gasoline is not.
Get a tune up if you have not had one recently. Bad spark plugs and wires eat up a lot of fuel.
Also, loose some weight. Carrying around junk in the trunk (bot h yours and your car's) costs you.
If you have big ugly roof racks or cargo carriers you should get that trash off the top when you don't need it. It doesn't look cool either.
Slow down to save gas. Drop a few miles per hour and watch your gas gauge drop a little slower. Pushing all that air aside at 70 miles per hour is a lot harder for your car to do than it is at 60 mph.
If all the above fails to save you enough it may be time to trade in your guzzler for a new ride that uses less fuel. Overseas they call our cars "Yank Tanks" because they use so much gas. In countries where they have been paying well over $5.00 for some time they wonder why we still drive such gas wasters. If you are getting less than 20 miles per gallon in the city it is time for a new car.
Hybrids like the Toyota, which your preachy, holier than thou sounding author drives get nearly 50 miles per gallon!
Don't worry about battery failure. There are Prius Taxis with over 250,000 miles on the original battery.
If a hybrid is out of your budget there are plenty gas and diesel burners for less like the Jetta, Accord, Ford Focus and others.