Until electrics and other types of multi or flex fuel vehicles become commercially available, people have to opt for the best green gas burning vehicles. Instead of plunking down some serious dough for a brand new gas-sipping auto, you can save a lot of money if you are willing to get a used car. I have made a list of the most fuel efficient used cars everyone can feel good about owning, while saving money and doing their part for the environment.

Toyota Prius - Next in line is the Toyota Prius. This one is a bit pricey as far as used cars go, so expect to pay anywhere from $12,000 to $20,000. However, you will get 44 miles per gallon in a car that has set the standard for hybrids. You'll sacrifice a little trunk space because of the battery pack, but everything else about this ride is comparable to any other regular car on the market.

Toyota Echo - Toyota scores another one here with the small, snappy Echo. Rated at 38 miles per gallon, they were made from the year 2000 until 2005. Depending upon the year, you can expect to pay from $3,000 to $10,000. It's a real Toyota, to be sure, and you can expect a roomy inside, good acceleration and good handling characteristics.

Honda Civic Hybrid - It looks like Hondas and Toyotas have the used car market pretty well wrapped up. Rated at 37 miles per gallon, a used Civic Hybrid is going to set you back between $12,000 and $20,000. But, it is a Honda, which is considered to be one the most reliable and bulletproof autos made.

Chevrolet Prizm - This is by far the least expensive car of the lot, but only because it has a Chevy bow tie on the front. (For your information, this is actually a Toyota Corolla, built in California up to Toyota quality standards, and sold as a Chevy.) It gets an estimated 32 miles per gallon. Expect to pay a measly $2500 for a good used example, so go and wave at some gas pumps while laughing on the way to the bank!

So if you want to save some green...and be green, drive one of these babies. You can't go wrong when you're driving to save the environment.