Oh, man, nobody does creepy atmosphere like you do. The opening scenes at the bridge gave a taste of it, but the way the wrongness of the time loop slowly snuck up on Sam was just spine-chilling. And the way Dean's story kept changing little by little, building up to that horrifying final version. I think the moment that got to me most, though, was the one where they look out at the horizon and realize that it's not actually a horizon. *shudder* That one's gonna stay with me for a while.