Our Facebook application has now been relaunched to make it even more fun for you and your friends to be a little bit greener.

The application allows you to issue challenges to your friends and to yourself to cut your carbon footprint. You can then keep track of how much CO2 you and your friends are saving, as well as telling you the equivalent amount of trees you've planted.

You'll also earn points for completing challenges and inviting friends to get involved, so you can battle it out to see who is the greenest of all your friends!

The application also shows what you and all your friends could accomplish if you just made small green changes. It really is amazing to see how much you can achieve by working together!

*Facebook is a registered trademark of Facebook, Inc.