Blackle
Following LiveEarth’s spirit, I will talk about the environment friendly search engine. No it’s not a completely new revolutionary search engine with complex algorithms, It’s just google washed up!
A monitor spends 74 watts average to display a white page while only 59 watts are spent to show a black page. Following this principle, Mark Ontkush posted that a Black Google would save 750 Megawatt-hours a year.
So go ahead, save our beautiful planet, just by changing your default homepage/search engine to Blackle
(note: I already suggested them to add OpenSearch so it could be easier for people to add it to their browser)

Paul Holstein