I visited the Google campus in Mountain View, CA on July 27-28, 2009 for the Google Affiliate Network Client Summit.
Some Google related trivia for you... I was an undergrad at the University of Maryland at the same time as Google Co-Founder Sergey Brin. However, I was in a fraternity and he was in a library, and I don't think our paths ever crossed.
More photos of the Google campus at www.flickr.com/photos/affiliate/sets/72157621872002024/