GF1: I always laugh out loud when Clemenza asks what Michael should do after plugging them both in the restaurant, and Michael casually replies "Sit down... finish my dinner."
GF2: The flashback scene when Sonny's daughter says "Mommy! Daddy's fighting again!"
GF3: When Michael is asked to confess his sins, and Michael responds with "I'd take up too much of your time." That's an extremely funny line, but many people don't catch the joke.
