So Harold Camping died. His was an interesting case: while I didn't think that the world was really going to end a couple of years ago (next year, however, watch out!), I never could muster up much hatred for the guy. If he genuinely believed that the world was going to end (and I think he did), and he genuinely believed that God wanted him to warn the world (and I think he did), then I have a hard time hating him for doing what he thought was necessary to get the word out. Was he wrong? Well, duh. But I don't necessarily think he was evil. Pilate's line from Jesus Christ, Superstar comes to mind: "He's just misguided/Thinks he's important."
Still, his predictions had, in some cases, dire consequences for his followers, which must be noted.