Now a new trend in ‘green’ search engines is raising money to fight global warming. Most of the search engines are powered using Google or Yahoo technologies and are committed to donating a percentage of money earned from advertising to charitable causes.

Popular environmental blog Treehugger recently carried out a survey of available green search engines, splitting them into three categories – those which donate a percentage of revenue to green causes, those which limit information returned to green products, and those which simply have an environmental slant.