• Carpool. Sure, we’ve heard this a million times, but “you could cut your transportation costs by half or more,” says Sarah Lippman, a spokesperson for the Clean Air Campaign, a Georgia nonprofit. What’s more, an environmental organization in your area might be willing to pay you not to drive alone. Clean Air, for instance, pays drivers $3 a day, up to $100 within a 90-day period, to carpool, bike, walk or take public transportation to work. Las Vegas has a program that lets you earn $5 to $50 in gift cards by logging in your carpooling time.
  
  
• Accessorize carefully. The iPod plugged into your cigarette lighter is no big deal, but windshield wipers and the defroster shouldn’t be overused. “As soon as they’re done doing their job, turn them off,” advises Clark. Individually, these devices don’t use up all that much gas, concedes Clark, “but they all add up.”
  
  
• Go easy on the air conditioning. Don’t turn it off if you’re baking — whatever you’ll save isn’t worth it — and keep in mind that rolling down the windows on the freeway won’t gain you much: The drag from the air rushing into the car could cancel out whatever gas savings you’re achieving by going AC-less. But in general the AC compressor is a huge drag on gasoline efficiency, and so if you’re driving around town at less than top speeds, lower those windows — or at least set the air conditioner to low.
  
  
• Check those gas-saving websites. Before you leave the house, check out websites that tell you what stations in your area have the cheapest gas. You can try Gasbuddy.com or FuelMeUp.com. There’s also the MapQuest gas prices site. It shows what stations have the cheapest gas — and how to get there.
  

Geoff Williams writes about business and personal finance. He lives in Loveland, Ohio.

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