Instead of using one of the big search engines like Google or Yahoo, consider using Ecosia.com instead. It works just like any other search engine to help you find what you need, but it uses its ad revenue to plant trees. When you make a search, targeted ads appear in the results -- like in any search engine. Revenue that's earned from those ads goes to plant trees all over the world. Since 2009, over 3 million trees have already been planted.