After doing a review of Green Rewards, I was told of another website called www.moreeco.com which also aims to reward people doing green shopping by giving them points to amass and then buy more green stuff with.
One way it differs from Green Rewards is that it gives you points for shopping at green stores only, rather than all, or a lot, of your online shopping. Also the rewards include some good stuff like planting a tree with your points.
I’ll investigate further and let you know how I find it. Also if you’re not reading enough at the moment, there’s a pretty cool blog with some interesting stuff on there. Called BeMoreEco, it contains some fun bits and pieces.