Om ni inte visste det finns Google med svart bakrund för att spara energi.

""…If Google had a black screen, taking in account the huge number of page
views, according to calculations, 750 mega watts/hour per year would be saved."

In response Google created a black version of its search engine, called
Blackle, with the exact same functions as the white version, but obviously
with lower energy consumption:

Help spread the word… use www.blackle.com http://www.blackle.com "