OK, I've got one:

Guy 1: Well, like Lenin once said...
Guy 2 interrupts: I am a walrus!
Guy 1: Erm.. What?
Guy 2: I am a walrus!
Guy 1: I said Lenin you dumba$$, not Lennon!

What movie?

Übereil

Brain: an apparatus with which we think we think.

Ambrose Bierce