DoGooder replaces regular ads with green ones, raises money for nonprofits
The funny part about the DoGooder is that you can give something back while you're doing naughty things on the web. Everyone knows that porn and torrent sites are some of the most ad-heavy properties on the web, but maybe you can feel better about visiting them when you're helping to raise awareness of green issues. The ads featured on DoGood are better than average in their design, and I definitely didn't see any egregious pop-ups or obnoxious ads with sound.
The DoGooder is available for Firefox, IE and Safari.