Have you heard about the Greenbagtag at CVS/pharmacy? For .99 cents you buy a leaf shaped tag to hang on ANY of your reusable bags - of course you can also purchase a bag from them as well. .05 cents from each bag purchase goes to World Wildlife Fund for every greenbagtag sold through March 31, 2011.
How the tag works: Each time you shop at CVS you scan your tag along with your ExtraCare card and you earn $1 in Extra Bucks AFTER every fourth purchase! The Extra Bucks money will appear printed on the bottom of your receipts so be sure to look at them and don't miss out on FREE money.
Be sure to visit their site at CVS.com for all the details. You'll be saving the environment and saving money all at once. You can't do any better than that! CVS, you're DOING IT RIGHT!