I'm a big fan of extreme green sports — death-defying activities that don't require tankers full of high-octane fuel to pull off. While it's true that very few sports come without any kind of negative environmental impact, it's easy to see how something like parkour or bouldering are kinder on the environment than riding dirt bikes or hill climbing.
One of my favorite greener extreme sports is wing suit proximity flying — hucking off a mountain and then boldly flying down its slopes using a wing suit and the ground effect. You might have seen Jeb Corliss's video "Grinding the Crack" sometime in the past year. If you haven't seen it yet, take a few minutes and give it watch.
And then spent a little more time watching this wonderfully shot short documentary about champion flyer Espen Fadnes and his crew.
Related post on MNN: 7 ultra-green extreme sports