The Wire reigns supreme when it comes to quotes like that! Like I said I love the dialogue on Deadwood, but The Wire just feels more real. Less literary allusions perhaps? ;)

I also love this one by Freamon:

Freamon: Ain't none of you ever been in the military? Don't you know how to make a 30-inch quick tie?
(Nobody speaks)
Freamon: Draft dodging peace freaks, huh?