"They become addicted to observing the cash costs of their driving habits," said Karl Singer, president of Fuel Efficiency Centers.
The Fuel Efficiency Adviser, he said, helps people measure their travel on a dollars-and-cents basis. On average, he said, it saves drivers 200 to 300 gallons or hundreds of dollars each year.
But, Singer continued, even though consumers may be driven by cash savings, they also become a part of the green movement.
"We started to get a lot of interest from people who are buying this as much for a green reason as they are an economic reason," Singer said.
3. Unplug when you can.
It's one of the easiest things to do: unplug.
Standby (or phantom) power, may be haunting your house -- and costing you more money on energy bills than you bargained for. Standby power eats up electricity on common appliances throughout your home while they're not even on. Seem unfair? Phantom power in the United States is responsible for 5 percent of the total energy used and $3 billion in actual dollars wasted, according to the Department of Energy.
Unplugging even the appliances you rarely use, like refrigerators in the basement, could save you about $10 every month on your utility bill.
Using power strips to switch off televisions, home theaters and stereos when they're not in use could save the equivalent to that of a 75 or 100 watt light bulb running non-stop, according to the NRDC.
4. Choose greener power.
Save energy even while you're plugged in. San Ramon, Calif.-based Green Plug recently announced the Innergie mCube 90G, a universal power adapter that eliminates the need for multiple chargers.
According to the company, each year consumer electronics companies churn out about 2.5 billion incompatible power supplies and dump another 700 million discarded products in landfills. Green Plug's one-size-fits-all approach attempts to reduce waste.
If you want to go one step farther, take a look at the nPower PEG, by Tremont Electric LLC. This futuristic device runs off of your own motion. With 15 minutes of walking you can charge your iPod just as much as it it was plugged in for 15 minutes -- with no plug needed.
5. Don't waste water.
Wasting water is an easy way to watch your money go down to drain. But there are several ways to fix this.
First off, take a minute and listen for the soft, "drip... drip," sound coming from your sinks or shower. The NRDC estimates that leaky faucets wastes about 3,000 gallons of water a year.
The organization recommends checking for a leaking toilet by placing food coloring in the tank and then waiting 30 minutes to see if it appears in the bowl. If it does, it's time to fix the leak.
You can also check for leaks by reading the water meter when no one is home and you know that no appliances are in use. If you check it a little later and the numbers have gone up, it could also indicate a leak.
Taking a four-minute shower instead of an eight-minute shower could also save almost 10 gallons of water. If you can't sacrifice that, replacing your water faucets with aerated ones will use less water without sacrificing pressure, and the cheap price of a low-flow shower head will repay itself in no time with the money it could save you in bills.
Have an out-dated iPod or computer? Is your cell looking a little tattered? You could make a buck selling it for cheap on Web sites like eBay, or you could give something back to the environment by recycling it.