Just because you're in the spy business doesn't mean you can't use some good exposure every now and then, especially if you're looking to recruit top talent in highly competitive areas like computer science and programming. That's the thinking behind a new online challenge from Britain's Government Communications, Headquarters (GCHQ) -- home to Her Majesty's Government Signal Intelligence, the U.K.'s main eavesdropping agency, the equivalent of the U.S. NSA -- inviting all comers to crack an alphanumeric code online, which leads them in turn to a recruitment center.