Louis has a bunch of these. When he's reminded there's a gun pointed at his heart: "That is my least vulnerable spot."
"How extravagant you are, throwing away women like that. Someday they may be scarce."
This exchange:
Ugarte: You despise me, don't you? Rick: If I gave you any thought I probably would.
And this:
Rick: How'd you get in here? You're underage. Young Woman: I came with Captain Rénault. Rick: (rolls eyes) I should've known... Young Woman: (primly) My husband is with me too. Rick: Oh, he is? Captain Rénault is getting broad-minded.
And this:
Louis: What in heaven's name brought you to Casablanca? Rick: My health. I came to Casablanca for the waters. Louis: The waters? What waters? We're in the desert. Rick: I was misinformed.
The "Blind Idiot" Translation of a couple of German refugees who have decided to only speak English, in preparation for moving to America.
Husband: "Liebchen— er, sweetnessheart... what watch?"
Wife: (checks time) "Ten watch."
Husband: "Such much?"
And Karl's reaction: "...You will get along beautifully in America."