Another book quote, this time from Soul Music. I have no idea what to say about this, other than that it's classic Pratchett. But what page of a Terry Pratchett book isn't? His books are very fractal that way.
Anyway, the passage:
"Lard. That'd the be the bacon smell," said the Lecturer.
"That's true," said Ridcully. "But what about the floral smell?"
"mumblemumblemumblelavendarmumble," said the Dean sullenly.
"I said it's because I added lavendar oil," said the Dean loudly. "And some of us happen to think it's a rather nifty hair style, thank you so very much. Your trouble, Archchancellor, is that you don't understand people of our age!"
"What... you mean seven months older than me?" said Ridcully.
This time the Dean hesitated.
"What did I just say?" he said.
"Have you been taking dried frog pills, old chap?" said Ridcully.
"Of course not, they're for the mentally unstable!" said the Dean.
"Ah. There's the trouble, then."
–Soul Music (Terry Pratchett)
This passage is an excellent example of dialog. There is exactly one five-word sentence of description in this passage. Everything else is either dialog tag or dialog. The dialog is interesting enough that it stands well without that. (I assume Terry gave a description earlier in this scene, but who knows.)