What role can social networking websites play in supporting large-scale group action and change? We are proposing to explore their use in supporting individual reduction in personal energy consumption. Here we summarize some existing uses of social networking on the web and propose an approach that integrates feedback about ecological footprint data into existing social networking sites and Internet portal sites. Integrating such feedback into popular, commonly used sites allows frequent feedback about performance, while enabling the exploration motivational schemes that leverage group membership. We propose to compare different motivational schemes in three ways: Reduction in CO2 emission; lifestyle changes; and ongoing use by users who join the site (retention).