Lots of different websites and applications let you rank results of searches. (Netflix, Pandora, etc.)
I think it would be a cool idea if Google did the same thing. When you get the top ten results, maybe you don’t like a certain website that they rank and you don’t want to see results from them anymore, you could give it a “thumbs down”. Once Google starts gathering data from people choosing their rankings, then they can personalize the results.