Climate-crusading charity Global Cool, whom we introduced introduced earlier this year, has enlisted the help of some eco-celebs to help spread the word about and inspire against global warming. Today, they're launching a new SMS-based campaign led by actors Sienna Miller, Josh Hartnett and Rosario Dawson; fans of the actors and consumers concerned about climate change are encouraged to sign up, via text message, for the campaign, which will feature exclusive content sent directly to users' cell phones. Through a partnership with MySpace, exclusive carbon-cutting messages will also be featured for one week within the ‘video exclusive’ section on the MySpace homepage on a rolling basis, promoting the Global Cool message to MySpace’s global audience. Joining the campaign will cost US users $3.99 per month and UK users £3 a month (not including network charges), and the proceeds will go to further Global Cool's work in mitigating climate change. See sample messages and sign up at ::their site or their MySpace. ::Global Cool

Thirsty for more? Check out these related articles:

Waterfight in Toronto: Who gets Water Day?

The 10 Most Magnificent Trees