The Guardian website has launched a new effort -- Tread Lightly.

From the introduction:

Do you want to live a more low-carbon lifestyle, but are unsure where to start?

Tread lightly is a community of people committed to reducing their CO2 emissions through making weekly pledges and recording their actions against their pledges.

This will enable people to step up their efforts to reduce their own CO2 emissions, and also to track the combined efforts of the community.