Taking a lesson from Digg and similar sites, Google Labs is testing out a new reader response interface for search results (with only a select few users for a limited time). Essentially, your normal search results are enhanced with "like it" and "don't like it" buttons that would tweak the order of said results on your list. And you can also add URL results that you would have liked to receive given your search premise. Google explains:
When you search for the same keywords again, you'll continue to see those changes. If you later want to revert your changes, you can undo any modifications you've made.
But your poor tastes/opinions won't screw everyone.
The system only works within browser...for now...meaning that your opinions will not affect other users. Of course, if such a system were deployed in a widespread fashion, we're guessing Google would aggregate data trends to alter search results over time for better relevance.