The digital age's most mundane act, the Google search, often represents layer upon layer of intrigue. And the intrigue starts in the sprawling, subterranean world of "black hat" optimization, the dark art of raising the profile of a Web site with methods that Google considers tantamount to cheating. Despite the cowboy outlaw connotations, black-hat services are not illegal, but trafficking in them risks the wrath of Google. The company draws a pretty thick line between techniques it considers deceptive and "white hat" approaches, which are offered by hundreds of consulting firms and are legitimate ways to increase a site’s visibility.