Blackle is the energy-saving search engine powered by Google.
How does Blackle save energy? Blackle saves energy because the screen is predominantly black. “Image displayed is primarily a function of the user’s color settings and desktop graphics, as well as the color and size of open application windows; a given monitor requires more power to display a white (or light) screen than a black (or dark) screen.” Roberson et al, 2002
Check it out and consider making Blackle your homepage.
Blackle.com – Saving energy one search at a time