A disaster that stops the planes where they're at. After all, my mother-in-law was stuck in Ireland over 9/11... was supposed to leave the Saturday afterwards, didn't leave until the Wednesday after that.

"You need me. You wouldn't be much of a hero without a villain. And you do love being the hero, don't you. The cheering children, the swooning women, you love it so much, it's made you my most reliable accomplice." -- Lex Luthor to Superman, Question Authority, Justice League Unlimited