The relationship between Vladimir and Estragon is like an old married couple, moaning and arguing with each other for years yet still sticking together.
Estragon's response when Vladimir asks him how's the carrot he's eating: "It's a carrot."
Estragon finds out that Vladimir's happy despite being separated from him for the night, especially because Vladimir's happy that he didn't have to get up at night to urinate.
Estragon: You see? He even pisses better when I'm not there.
Early in Act 2, Estragon tries to recount to Vladimir what happened yesterday:
Estragon: I suppose we blathered.
Vladimir: About what?
Estragon: Oh...this and that, I suppose, nothing in particular. [With assurance.] Yes, now I remember, yesterday evening we spent blathering about nothing in particular. That's been going on now for half a century.
The hat-swapping scene in Act 2.
Vladimir and Estragon going round in circles, muttering "Let me see".
Lucky's long, deep-sounding but entirely meaningless rant when he finally starts talking.