So you're ready to get a new car. Congratulations on your reentry into financial enslavement.

Interested in reducing that enormous burden of guilt you carry with you as you spew hydrocarbons around town?

Here are our suggestions:

I. Don't buy an SUV--unless you really need one
II. Buy an efficient conventional car
III. Try A Hybrid

I. Don't buy an SUV. Unless you really need one. (And there are very few people who really need one, in our humble opinion.)
Tree-Hugging Factor: 4 out of 5 trees

Our most important piece of advice is this: Don't buy a car that's bigger than your needs. In other words, don't buy a Lincoln Navigator unless you really need something the size of the Titanic on a routine basis.

If you haul a boat around for two weeks each summer, or if you like to load up the car with your kids, in-laws, and hitchhiking prison escapees, rent a car for those two weeks instead. You'll save money on insurance, fuel costs, and maintenance. You'll find it easier to park during the other 50 weeks, and you won't be stinking up the planet.

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II. Buy an efficient conventional car.
Tree-Hugging Factor: 4 out of 5 trees

Buying a fuel-efficient car is one of the easiest ways to reduce damage to the environment. Not only will you lessen all kinds of noxious emissions into the air, but smaller cars also use fewer raw materials in assembly. That means that building a fuel-efficient car creates less pollution than building a road monster.

So who's keeping track of the most politically correct new cars? The ACEEE, the American Council for an Energy-Efficient Economy. (But you probably already knew that, right?) The ACEEE factors in both tailpipe emissions and fuel economy when ranking new vehicles.

Here's the ACEEE's 2005 list of the top 12 granola-friendly conventional cars - that is, the ones you put gas in, not compressed natural gas, a 50-mile-long electric cord, or beaver dung:

And - far more entertaining - here are the big losers for 2005:

If you honestly require one of these cars, that's fine. But, if you don't, and you buy one anyway...we'll personally dope-slap you for unwarranted spewing of emissions - and for endangering the rest of us on the roads.

You can use an interactive version of the ACEEE ratings to check out the environmental score of the cars you're interested in. Or, head over to the Environmental Defense Tailpipe Tally. Just give the Tailpipe Tally a year, make and model, and you'll get back a complete rundown on the economic and environmental costs.

Another great guide for efficient new cars is the Environmental Protection Agency's Green Vehicle Guide. Tell the guide what kind of car you're looking for, and it'll give you the best choices in that category. You can also compare vehicles, check emissions ratings, and peruse the overall ratings. Suggestions list

III. Try A Hybrid.
Tree Hugging Factor: 5 out of 5 trees

For the first time since Karl Benz was in diapers, there's also a fundamentally new, extremely fuel efficient engine design: Hybrid Electric Vehicles (HEVs), also known as hybrids.

How do they work? A hybrid uses both a small gasoline engine and an electric motor to power the car. And the batteries for the electric motor are charged by the gasoline engine, so you never have to plug it in.

The result of this design is a significant increase in fuel economy and a significant decrease in pollution, compared to their counterparts with traditional engines.

Right now, a number of hybrids are available, most notably the Toyota Prius, and the Honda Civic Hybrid. Many more are on the way in the next year or two. You'll save boatloads of money on gas, and purchasers of a hybrid will be able to claim a deduction of $2,000 for the year that the vehicle was first put into use.

IV. Buy a used car.
Tree-Hugging Factor: 2 trees

The car-manufacturing industrial complex is the largest source of industrial pollution on earth. It's been said that purchasing a new car is the single most polluting thing you can do in your life. (Of course, whoever said that never saw Tommy clean out his basement.) By buying a used car, you'll cut down on all kinds of resources used in the manufacturing process, you'll save a nice chunk of money, and you'll be reusing something that would otherwise get ground up and mostly deposited in a landfill.

For used cars in your 'hood, check out cars.com.

If you're getting rid of your old heap, consider donating it to a worthy cause. Your car will get reused, and you'll be able to take a few bucks out of the IRS's coffers in the process.

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