Community Service 2009

So far, RecycleBank has enlisted more than 1 million people in 20 states to help save the planet by padding their wallets. "That's our value proposition: we're going to make it financially attractive to recycle," says Ron Gonen, who co-founded the for-profit company in 2004 while enrolled at Columbia Business School. Participants receive a container with a computer chip embedded in it that weighs the amount they recycle and rewards them with points that can be redeemed at more than 1,500 retailers, including Target.com and Bed Bath & Beyond. The system, which lets consumers earn up to $400 a year, makes for a nice little curbside pick-me-up.

See pictures of the world's most polluted places.