At the Searchology event, where Google talked about its history and launched some major new features, a slide caught my attention: this is the World Wide Web* today, or probably the most important sites and the links that connect them. Too bad we can't see the address for each node.
* "The World Wide Web (or the Web) is a system of interlinked, hypertext documents that runs over the Internet. With a Web browser, a user views Web pages that may contain text, images, and other multimedia and navigates between them using hyperlinks." (Wikipedia)