Google has this habit of testing out new features without so much as a peep. Just today, I discovered this: an option to search the "I'm Feeling Lucky" site (for sites that offer additional options below the main search hit) from within the main search results page.
Nice. Saves me the effort (sometimes) of doing a "site:example.com" manually. I don't think that site would like it too much though, as it could detract from their pagehits.