Ten years ago, Christian Kroll founded the Ecosia search engine as an alternative to Google. Its mission statement was simple: use its profits to plant trees - millions of them.
The idea is without a doubt revolutionary. A search engine whose servers run on 100% renewable energy, from its own solar power plant. All data is anonymous (check privacy policy) and is deleted every week and 80% of the income obtained is used to plant a tree. It's about Ecosia.