Zombies are are huge moneymakers. In fact, 24/7 Wall Street estimates the walking undead generate more than five-billion-dollars in annual DVD and movie sales, video games, comic books, costumes and other merchandise.  The financial blog points to the success of the four "Resident Evil" films and "Pirates of the Caribbean" franchise as helping propel the zombie genre well beyond its early cult status.  Video games like "Doom," "House of the Dead" and "Call of Duty" also get credit for stoking public interest.  The blog predicts the already widespread appeal of zombies is only going to get larger.