Sydney-based Ecocho founder Tim Macdonald had an idea; build a search engine based on Google and Yahoo technology and use the ad revenue to plant two trees for every 1,000 searches, offsetting tons of carbon dioxide.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/google-ends-eco-search-engine-support
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/environment-news-network-us
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/environment
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-dioxide
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/science-and-technology