In the exciting world of today's Internet, where the world's information is literally at your fingertips, where you can endlessly communicate, shop, research, and be entertained, spam is a big downer. The unwanted email spam that fills our inboxes also consumes huge portions of the available bandwidth of our routers and trunk lines. But email is not the only spam game in town. Web spam is the bane (well, one of the banes) of the search engine and web searcher communities.