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DCL
Real Costs is a Firefox plug-in that inserts emissions data into travel-related e-commerce sites, including airfare Web sites such as AmericanAirlines.com, Delta.com, Orbitz.com, and United.com. (Versions for car-direction, car-rental, and shipping Web sites are the pipeline.)
Once installed, the Real Costs plug-in pulls data from your travel selections at any of the nearly 30 supported sites to calculate how much carbon dioxide your proposed flight will produce. This information is inserted next to the flight you've picked, along with a graphical comparison of the carbon emissions you'd save if you made that trip by bus, train, or carpool, as well as other metrics such as the average carbon dioxide produced per capita by various world travelers.
And, If you're not writhing with guilt yet, a bar with the number of tree-years it'd take to neutralize your emissions has also been thoughtfully included. "Think of it like the nutritional information labeling on the back of food," say the plugin-in makers, "except for emissions." ::The Real Costs
Difficulty level: Easy
