Sunset Boulevard (1950)
A:      Joe Gillis (William Holden)
B:      Norma Desmond (Gloria Swanson)

A:      You’re Norma Desmond.  You used to be in silent pictures.  You used to be big.
B:      I am big.  It's the pictures that got small.
A:      Uh-huh.  I knew there was something wrong.
B:      They’re dead!  They’re finished!  There was a time in this business when they had the eyes of the whole wide world, but that wasn’t good enough for them.  Oh, huh, no.  They had to have the ears of the world, too, so they opened their big mouths, and out came talk, talk, talk!
A:      That’s where the popcorn business comes in.  You buy yourself a bag and plug up your ears.
B:      Look at them in their front offices, the masterminds!  They took the idols and smashed them-- the Fairbankses, the Gilberts, the Valentinos!  And who have we got now?  Some nobodies.
A:      Don’t blame me.  I’m not an executive, just a writer.
B:      You are?  Writing words, words, more words.  Well, you’ve made a rope of words and strangled this business.  Aha.  But there’s a microphone right there to catch the last gurgles and technicolor to photograph the red, swollen tongue.
A:      Shh!  You’ll wake up the monkey.
B:      Get out!  Max!
A:      Next time I’ll bring my autograph album along, or maybe a hunk of cement and ask for your footprint.

This line is #24 in AFI's 100 Years... 100 Movie Quotes.