GoZero -- Allows you to convert your air travel to carbon neutral. You make a donation based on miles flown, they plant the equivalent number of trees to zero you out.
My recent roundtrip Houston-New York City trip cost me US$ 7.50.
GreenDimes -- Removes you permanently from junk mail lists, and every month you're a member, plants a tree on your behalf. Woohoo!
Kiva.org--Matches you to third world artisans and entrepreneurs -- give as little as a US$ 25 'microloan' to help.
Enjoy!
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