Just a quick educational video here, folks. Just when you thought The Google couldn't get any better, it has. This video shows how the company has just expanded its results page to give you a variety of options to further refine the search.
Sound boring? It really isn't. And check out when he talks about the Wonder Wheel option.
(And an unrelated trick: If you add the word "wiki" to your search, the Wikipedia entry will be the first one returned by Google.)