I’ve just added this widget to measure your site’s CO2 emissions.

The CO2Stats Project freely distributes a widget that calculates your web site or blog’s carbon footprint in real-time due to the total electricity usage of your readers’ computers as they spend time on your site. The Project then offsets your popularity by purchasing carbon credits from a provider listed below. The Internet is responsible for more than 100 billion pounds of CO2 emissions per year, yet most users are unaware of its environmental impact. Founded by Ph.D. students at Harvard and Yale, The CO2Stats Project has the ambitious goal of making the entire Web carbon neutral!

It’s been featured on Mashable. And it is on my left sidebar. Go check it!