Digerati and creative minds of all stripes and backgrounds are gathered in Maine this week for Pop!Tech, one of the coolest conferences around. (You might call it TED before it got too focused on established celebrities at the expense of bold new ideas.)

This isn't just some talkfest in which smart, important people meet other smart, important people, exchange business cards, and pat each other on the back. Today, Pop!Tech launched a carbon offset initiative with eBay. At a special eBay online store, you can calculate the rough amount of carbon you put into the Earth's atmosphere and then choose between three projects that will not only compensate for your pollution, but also do some good in their own right. Learn more about the initiative here or just head straight to the checkout counter.