Blackle – The Environmentally-friendly Google

Whenever your PC screen is all white (as in a Word page for instance) the computer will consume about 74
watts. When black it uses an average of 59 watts. Using this knowledge, some months ago, Mark Ontkush
wrote an article about how much could be economized if a Google page used a black background instead of
white. Taking into account the enormous popularity of the site, according to Mark's calculations, about 750
megawatts/hour would be economized each year. Using this data Google created an all dark version of his
search engine calling it Blackle that works exactly as the original version but consumes less power.

http://www.blackle.com