The following passage from Stephen King and Peter Straub's Black House is a favorite of mine. Usually I don't like my foreshadowing quite this blatant (I prefer the "sucker punch" approach to Bad Things Happening to Good Characters), but something about this passage resonates with me.
Still, they are safe. And our guys are safe, too. All of them came back in one piece from the other side, and surely we did not expect that; most quests of this type usually demand at least one sacrifice. All's well that ends well. And this can be the end, if you want it to be; neither of the scribbling fellows who have brought you this far would deny you that. If you do choose to go on, never say you weren't warned: you're not going to like what happens next.
Ooooh, yes! And you know what? They were right!
* Stealing an idea from the Pub Rants blog. Agent Kristin starts every blog entry with what she's listening to at the time, and since I don't talk about music enough on this blog, I'll follow suit.