Another day, another carbon calculator. But wait, this one is different, says Chris Jones, who developed the CoolClimate Calculator for the University of California at Berkeley's Renewable and Appropriate Energy Laboratory and the Berkeley Institute of the Environment. Few of those calculators collate everything people do that contributes global-warming carbon emissions, he tells Discovery News.

The CoolClimate Calculator, on the other hand, factors where you live, since local and regional climate can have an impact on how much heating and cooling you do in your home, in addition to how many miles you fly each year, how much you drive, and what foods you eat. "We were able to incorporate these types of data," says Jones. "We know the consumption habits of the top 28 metropolitan areas." (For the rest of us, the calculator uses regional averages.)

One thing you can expect in the future is a way to account for any carbon offsets, Jones says. ::CoolClimate Calculator

Difficulty level: Easy