Black Isle FTW:
"Fool me once, shame on you. Fool me twice, watch it! I'm huge!" Minsc from Baldur's Gate
"I estimate Fall-from-Grace to be found attractive by the male sex of over 321423 separate species. Give or take 5." Nordom from Planescape: Torment
"There is safety is numbers. And I'm two or three at least." Minsc from Baldur's Gate
"You are amusing... in a what the hell is wrong with you kind of way." Jaheira of Baldur's Gate
"Attention: Morte. I have a question. Do you have a destiny? A purpose?"
"Is Annah still wearing clothes?"
"Affirmatory."
"Then the answer is yes." Morte and Nordom of Planescape
"I thank you for not stealing the pantaloons, and I will thank you kindly not the mention the stuffing in the codpiece." Nobleman (upon actual quest completion) from Baldur's Gate
"Elminster this, Elminster that, give ME 2000 years and a pointy hat and I'll kick his arse!" Edwin from Baldur's Gate
"Morte, I'm curious... what happened to your body?"
"It's a long story involving the Head of Vecna. I don't want to talk about it."
(laughing) "That was you?"
"Could we *please* change the subject?" Morte and Fall-from-Grace of Planescape
And to top it off, some great lines you get to say as the protagonist in Baldur's Gate 1 and 2:
-I know you said that you wouldn't tolerate excuses, but we have a real good one.
-Forsooth, methinks you are no ordinary talking chicken!
-Sorry, Aldeth, but we're siding with the druids. They have this great Aloe-Vera balm they are giving away samples of, and my armor has been chafing a bit, ya know?
-No, we're not mercenaries. We just carry weapons and kill things for the joy of the experience.
-Ok, I've just about had my FILL of riddle asking, quest assigning, insult throwing, pun hurling, hostage taking, iron mongering, smart arsed fools, freaks, and felons that continually test my will, mettle, strength, intelligence, and most of all, patience! If you've got a straight answer ANYWHERE in that bent little head of yours, I want to hear it pretty damn quick or I'm going to take a large blunt object roughly the size of Elminster AND his hat, and stuff it lengthwise into a crevice of your being so seldom seen that even the denizens of the nine hells themselves wouldn't touch it with a twenty-foot rusty halberd! Have I MADE myself perfectly CLEAR?!
-For your information, a number of important sociological and psychological theorists have posited that stores exist in an intermediate space, neither private nor public in nature but combining elements of both. Displays in store windows, for instance, can best be viewed as mental constructs projected onto the public consciousness as a means of engendering mass conformity derived solely from the supposedly private domain of consumer choice..........
-Why are you so fat?
-Utterly amazing! You spoke so long, but you didn't say anything.
-You know what I always say? "Always kill the mouthy one", that's what I always say.
-Thank you for the compliment. Shall we kill you now or would you rather beg for a time?
- I am Dinkamus Littlelog and I come in search of the holy groundhog.
-(When caught stealing) DIE! POND SCUM!
- We're a horde of rampaging Tarrasques! Krie! Krie!
- So, did your parents like trees?
- I am Foolio Displasius, Destroyer of the Seven Suns! Raagh!
-Poor little gnome. My heart bleeds. Yours will too.
- I'm going to go out on a limb and guess it's my job to get everyone out from this "trap".
-Fine, I'll do all the actual work. As usual.
-(To Minsc) You stand as inspiration. You are practically the Avatar of Buttkicking.
- Is it true that dragon meat tastes like chicken? Never mind, I?ll find out for myself.
-We all know this is going to end in violence. Let's just cut right to the good stuff.
-Maybe your grandiose vocabulary is a pathetic compensation for an insufficiency in the nether regions of your anatomy