Baldur's gate had a LOT of good ones. Here are a few:
(to a gnome raising basilisks)Is it just me, or is the world filled with wackos? Okay, Mr. Psycho gnome, I hope you don't take this the wrong way, but we're really not interested in your rock garden
Mellicamp the Chicken: Th... thank ye... (cluck). You have saved (cluck) me.
Protagonist: A-a-a-ah!!! Unholy magics are afoot! This chicken is possessed! This bird is FOUL!!!
Guard: You wouldn't kill a man with a wife and ten children, would you?
Protagonist: No way, you've got a fate worse than death already.
Jan: You know, Binky, I have been considering this plan of yours that you had with the Iron Throne and all that. Interesting ideas... but flawed.
Sarevok: Binky? You had best not be addressing me, gnome.
Jan: For instance, whose idea was it to put impurities in the iron? Sounds like the lame idea of some yes-man underling who didn't know when to quit. No doubt you had him flogged.
Sarevok: I will not have my past commented upon by the likes of you, churl. Quiet yourself, lest that you experience more than mere flogging.
Jan: Speaking of a good flog, I'm brought to mind of poor Auntie Sara. She, too, had a master plan to take over the Sword Coast, you know. Although hers was considerably less dramatic and involved the use of some tasty recipes for a turnip pie and some mind-altering herbs that Auntie Sara had bought from a rather disreputable Turmish mage.
Sarevok: Are you listening of *nothing* I say?! Desist or suffer the consequences!
Jan: Do you think she would listen to us? You can trust a Turmish mage about as far as you can kick him... and even then it's not a bad idea to carry a good thumping stick. But, alas, Auntie Sara just cackled in her most villain-like way and was determined to carry on with her plan to hypnotize the Sword Coast. Alas, she was compeletely undone by an over-the-top exposition she gave to a spy she had captured... and who subsequently escaped, of course, before she could have him killed. It's what villains do, I understand, when they're not busy defiling iron.
Sarevok: I will not be mocked, gnome! This is your last warning!
Jan: Of course, they say that Duke Eltan had already had a bit of Auntie's pie and enjoyed it immensely. Rather than becoming hypnotized, he just became rather pleasantly obsessed with silken undergarments. This, of course, led to the first Great Underwear Shortage. It's also known as the Three-Year Wedgie Drought, but that's another story completely.
Sarevok: AUUUUGHHH!! How maddening! How can you put up with such impudence, ?!