Green (ish), keen (definitely) -- Perrier-winning Mark Watson is halving his carbon footprint and, in Danny Wallace Join Me-"style, he's taking you with him.

What the environmental movement really needs is a hard-travelling, blissfully ignorant comedian with no credibility whatsoever to talk on serious issues. No seriously. On the principle of 'go on, do it, I will' non-expert Mark Watson set up a blog announcing his intentions to halve his carbon footprint in a year. Within 24 hours, 500 had joined him. This is the story of the year that followed, when one environmental novice, green you could say in all senses of the word, tried to save the planet.