LMAO!! Francis McDormand cracks me up. "You've gotta get his dip-tep!"
Even though it has Clooney in it, I've got to go with O'Brother for my favorite. I just love everything about it. Favorite line: "And stay out of the Woolworth's!"
Oh I forgot another favorite line from Raising Arizona: The old man counting to a 100 behind the counter, “Aw ... bullsh#t.” :)