I just found this site: Earthle
What is Earthle?
Earthle was created with the idea in mind to save your energy and reduce your electricity bill.
According to the creator, all white web page uses about 74 watts to display, while an all black page uses only 59 watts.
Extract from Earthle:
Take at look at Google, who gets about 200 million queries a day. Let’s assume each query is displayed for about 10 seconds; that means Google is running for about 550,000 hours every day on some desktop. Assuming that users run Google in full screen mode, the shift to a black background will save a total of 15 (74-59) watts. That turns into a global savings of 8.3 Megawatt-hours per day, or about 3000 Megawatt-hours a year. Now take into account that about 25 percent of the are CRTs, and at 10 cents a kilowatt-hour, that’s $75,000, a goodly amount of energy and dollars for changing a few color codes.
You may say, Google is my preferred search engine.
Don’t worry, when you search using Earthle, the results are powered by Google so the search results provided by Earthle are the same as what you would get using Google.
Really interesting concept, I must say.