It's probably been all over the internet a million times already, but I can never get enough of Dom Deluise as Buddy Bizarre conducting "The French Mistake" in Blazing Saddles - pure heaven.
Buddy Bizarre: What in the hell do you think you're doing here? This is a closed set.
Taggart: Piss on you! I'm working for Mel Brooks.
[winds up to punch Buddy]
Buddy Bizarre: Not in the face!
[Taggart punches Buddy in the stomach]
Buddy Bizarre: [collapsing] Thank you...
Buddy Bizarre: Is everybody ready?
[the actors answer with a heavily lisping "yethhhh"]
Buddy Bizarre: Sounds like steam escaping.