What do you guys (and girls) think about books? What book did you read that spoke to your fear the most?

Personally, I was the most horrified by Peter Watts' "Starfish". Jesus, the book might be sick but the underwater stuff is the worst. There is a scene where the protagonist goes out into the absolute darkness of the deep sea, thinking, and suddenly feels something big swimming by. No problem Watts, the sea can't make me much more uncomfortable anyway.