You could opt for the latest hybrid or diesel models, or even an electric car like the Nissan Leaf.
But if those are a little outside your comfort zone, you could do worse than to look at the latest generation of traditional gasoline-powered compact cars--all of which now boast combined MPG figures in the mid 30s and over 40 mpg highway.
Listed below are the top five most efficient compact cars on sale. Diesels, hybrids or battery electric vehicles may be even cheaper to run, but each car below should improve over your current car without much effort.
1. 2014 Honda Civic HF
35 mpg combined (31 mpg city, 41 mpg highway)
Honda has long been known for its gas-sippers, and while it's dropped the baton lately when it comes to desirability it's still a Civic that tops this list.
It trades economy figures with the Corolla LE Eco, but pips it on the EPA's Fueleconomy.gov website on account of its better city figure. At $20,730 (including Honda's $790 destination charge) it's a little more expensive than the Corolla, but it's a good four grand cheaper than the 45 mpg Civic Hybrid.
2. 2014 Toyota Corolla LE Eco
35 mpg combined (30 mpg city, 42 mpg highway)
Like the Honda above, Toyota's Corolla LE Eco uses a 1.8-liter gasoline four-cylinder, and comes with a continuously-variable transmission to maximize economy.
Also like the Honda, it's not the most interesting car to drive. But it does match the best highway economy here (that of the Cruze Eco) for a reasonable $19,905 including destination fees.
3. 2014 Mazda 3
34 mpg combined (30 mpg city, 41 mpg highway)
While its Japanese rivals are worthy but dull, Mazda has gone to town on the new 3's chassis--it's a hoot to drive.
That's not at the expense of fuel efficiency either. With specially-designed 'Skyactiv' engines Mazda boasts some of the best gas-mileage in the class, and the car's 2.0-liter engine offers more performance than the 1.8s of its rivals. Opt for the manual transmission and it's even more fun--though does drop 1 mpg from the combined figure.
4. 2014 Nissan Sentra FE
34 mpg combined (30 mpg city, 40 mpg highway)
After a brief foray into style and excitement with Mazda's 3, the Sentra marks a return to the 'worthy but dull' mantras of its Honda and Toyota rivals.
The CVT (like the Honda and Toyota but unlike the Mazda) has been tuned for peppy low-down response but its main priority is economy. Advancements made by the other Japanese makes leaves it trailing a little, but at $18,050 (including $810 destination and handling) it's also cheaper than the others by almost two grand.
5. 2014 Chevrolet Cruze Eco
33 mpg combined (28 mpg city, 42 mpg highway)
Had this been a list of six vehicles, the 2014 Dodge Dart Aero would also have featured. But in a class of five, it's the Chevy Cruze Eco left holding the American fort--with one of the best highway mileage figures here.
The Cruze is also the odd-one-out here offering a manual transmission, though combined mileage only matches that of the manual-equipped Mazda. But the manual 'box gives it a peppy feel and with a skilled driver, the potential for even greater fuel efficiency. Pricing begins at $20,760 including destination.