From Princess Bride
Vizzini: "HE DIDN'T FALL?! INCONCEIVABLE!!"
Inigo: "You keep using that word. I do not think it means what you think it means."
Vizzini: "You only THINK I guessed wrong! That's what's so funny! I switched glasses while your back was turned! Ha ha! You fool! You fell for one of the classic blunders! The most famous is never get involved in a land war in Asia, but only slightly less well known is this: never go in against a Sicilian when death is on the line! Ha ha ha ha ha ha ha! Ha ha ha ha ha ha ha! Ha ha ha -" (Vizzini drops dead.)
From Casablanca:
Ugarte: You know, Rick, I have many a friend in Casablanca, but somehow, just because you despise me, you are the only one I trust.
Major Strasser: You give him credit for too much cleverness. My impression was that he's just another blundering American.
Captain Renault: We musn't underestimate American blundering. I was with them when they blundered into Berlin in 1918.
Captain Louis Renault: What in heaven's name brought you to Casablanca?
Rick Blaine: My health. I came to Casablanca for the waters.
Captain Louis Renault: The waters? What waters? We're in the desert.
Rick Blaine: I was misinformed.
From The Maltese Falcon:
Sam Spade: The chances are you'll get off with life. That means you'll be out again in twenty years. You're an angel. I'll wait for you. . . . If they hang you, I'll always remember you.
ZV