Ooh! Fun lines are the stuff of my Goodreads reading status updates.
"No, no assassins yet. I guess I've already got too much chull sass of my own." -Wit, WoK p.326 UK ed.
"You're so conservative that even your socks are more traditional than the rest of us." -This one's from Elantris, but I forgot to note who said it, and what page number.
"I hope you Free Kingdomers aren't too put out to discover that dragons didn't come and bow to me at my birth. I wasn't tutored by the spirits of my dead Smedry ancestors, nor did I kill my first Librarian by slitting his throat with his own Library Card." -from Alcatraz Versus The Evil Librarians
"Now I've already spoken about foreshadowing (a meddling literary convention of which Heisenberg would uncertainly be proud.)" -Also from Alcatraz #1
"You see, that is the sad, terrible, sorry thing about sarcasm. It's really funny." -Again, from Alcatraz #1
“War is far worse. At least where politics is going on, there are
usually nice hors d’oeuvres.” -Warbreaker