Let's get something straight right off the bat. You will not increase your gas mileage by consolidating trips to the supermarket, or doing several errands on the same excursion, or using mass transit, or riding a bicycle. These are excellent suggestions to reduce the amount of fuel you use, but they do not change the miles-per-gallon (MPG) your vehicle gets.
There are only two ways to increase gas mileage; change your car in some way, or change the way you drive.
Get a New Car?
Buying a more fuel-efficient car can make sense if done right. Trading in a gas-hog SUV with big monthly payments and less than a year of the loan remaining, and getting a used fuel -efficient auto would make sense financially and improve your fuel economy. If you're a good negotiator, you could drive away from the lot with a good car, a 5 year warranty, and maybe a check in your pocket!
But this scenario is unlikely, because most prestige SUV owners have these vehicles to stoke their egos, not for the financial or practical sense they make.
On the other hand, selling your paid-off Acura and getting a hybrid would probably be a bad move. Having a car payment would far outstrip the fuel savings for years, and leave you spending more money, instead of saving. Sure, it would increase your gas mileage, but at what cost?
If you lease your car, switching to a more economical model would make good sense when your lease is up. But switching while your lease is in force would cost more than the fuel savings would be worth.
In most cases keeping your current car makes the most sense. But there are other tried-and-true ways to increase your gas mileage.
Tire Pressure
Check your tire pressure often, and keep them inflated to near the maximum rating. With lower tire pressure your tires "squash " a little where it hits the road, reducing the radius from your axle to the road surface. An inch of squash reduces the "rolling circumference" of your tire by about six inches. So what?
Well, here's a (slightly technical) example. An 8" tire on a 16" rim has a radius of 16". The cirumference is around 100" (100.48 would be more precise, but I'm rounding). A 15" radius with low air pressure reduces the circumference to 94", meaning that every revolution of the wheel moves you 6" less, a decrease of about 6%! This would make a 20 MPG vehicle get less than 19 MPG.
Of course there are other factors involved, but this simple mathematical fact demonstrates the effect proper tire.
Don't Lead Foot the Gas Pedal
Accelerating quickly, or just plain revving up at a stop light, is very wasteful and will use up gasoline like you wouldn't believe.
Driving on the highway can be quite nerve racking, especially if everyone else is speeding. Of course, everyone else is burning more fuel too, so set an example and obey the speed limit. By doing this, you will increase your gas mileage like nobodies business.
Take a look at your driving habits. Try not to weave in and out of traffic, or drive with your foot on the brake pedal. Any kind of erratic driving behavior will cost you more money and maybe someone's life.
Standard transmission vehicles are much cheaper to run, both in repairs and gas economy. However, driving with a poor speed-ratio will burn more gas and oil, and will be harmful to your engine.
Conclusion
If you really want to save some serious money, then maybe you could car pool with your work associates, or even car pool errands with your neighbors. In fact, by cutting back and thinking of alternative ways to save money on gasoline, you will inadvertently be increasing your gas mileage and turning your neighborhood a little greener.
