You know something has changed in America when people are suddenly talking about walking or biking to work and forgoing vacations that require long drives. A newcomer to our country might wonder what's up, but you and I know that it's the price of gas. It has skyrocketed so much, so fast, that our heads are spinning. Each time we fill up, we get a sick feeling in the pit of our stomachs. And many of those who drive gas-guzzlers are looking at alternatives.

If you're driving an eight-cylinder Ford (NYSE:F) Expedition, for example, your gas tank holds about 28 gallons. Each time you fill up, it can cost you $75 or more! Worse still, your miles per gallon aren't too impressive, so you're forking that $75 over more often than you might like.

Fortunately, you have choices. Here, from Edmunds.com, are the top vehicles in terms of fuel efficiency, based on the Environmental Protection Agency's miles-per-gallon ratings. The numbers below represent miles per gallon for city and highway driving, respectively.

  • Honda (NYSE:HMC) Insight -- 61/66
  • Toyota (NYSE:TM) Prius -- 60/51 (automatic transmission)
  • Honda Civic Hybrid -- 45/51
  • Volkswagen Golf TDI -- 38/46
  • Volkswagen Jetta TDI -- 38/46
  • Volkswagen New Beetle TDI -- 38/46
  • Honda Civic HX -- 36/44
  • Toyota Echo -- 35/42
  • Toyota Corolla -- 32/41
  • Scion xA (by Toyota) -- 32/37
  • Honda Accord Hybrid -- 30/37 (automatic transmission)
  • General Motors' (NYSE:GM) Pontiac Vibe -- 30/36
  • Toyota Matrix -- 30/36
  • Scion xB (by Toyota) -- 31/35 (automatic transmission)
  • DaimlerChrysler's (NYSE:DCX) Dodge Neon -- 29/36
  • Toyota Celica GT -- 29/36 (automatic transmission)

Don't rush out and buy just any of these, though. Know that some of them are in high demand and may be hard to find or may command steep premium prices. While it would be much more satisfying to save 50% on your gas expenses, keep in mind that it still might not be enough to make the vehicle exchange worth it. Consider factors such as what the car you're getting rid of is worth and what it will cost to buy your new vehicle. If it will take you five years to come out ahead, think twice, as the price of gas may well settle down in a year or two. (Or not. I'm not predicting anything here.)

One upside to buying an energy-efficient vehicle is that there are tax credits available for some of them.

If you do want to investigate the possibility of getting a new car, do your homework. You can learn more about buying a car by going to our Buying a Car area. (Check out our Insurance Center, too. It also offers a lot of money-saving tips.)

What are your thoughts on fuel-efficient cars? Share your thoughts on our Buying and Maintaining a Car discussion board. Or just pop in to see what others are saying. (We're offering a free 30-day trial of our entire discussion board community right now.)

Finally, here are some articles of possible interest:

Longtime Fool contributor Selena Maranjian does not own shares of any companies mentioned in this article.