You stand before the rust-stained, 30-foot-tall iron gates protecting the sprawling, softly-glowing metropolis of Nuketown. A guard peers down at you, squinting in uneasy twilight, coughs heartily, then says "Eh? Want in? 'Kay. Not a problem. All you need to do is register with the Administrator."
"You fill out this form, I take it to the Man, and he decides whether you're worthy of admission ... or whether you're one of those gorram spammers trying to squirm their way in again. Mutants? We don't care about mutants, but spammers ... we string those bastards up from yonder Tree of Woe." So fill out the form -- make sure you get all them required fields -- and the Administrator will approve you damn quick. You'll get two messages from the ol'thermonunclear burg -- the first gives you your username and password, but don't let you in. The second says the Administrator's done approved you; once you get the second one, you can use the information in the first to get in.