Chosen One: Uh... doggie talk? K-9: One; I am a dog. Two; I am communicating with you vocally using the common English language. Therefore it is safe to assume that the answer to your question is 'yes, doggie talk.' Now, do you intend to answer the question that I posed to you a moment ago? Chosen One: Sorry, me forget question. K-9: (sighs) Pay attention. Concentrate. Look me in the eyes. Now, are you ready? Chosen One: Ready what? K-9: I... If it were not for the fact that your IQ is less than my height in feet I would think that you are trying to irritate me. Now, be silent. Pay attention. Concentrate. Look me in the eyes. I am about to ask you a question.
Sulik's reaction to meeting a low-intelligence character:
Sulik: Most people have evil spirits. You? You have stupid spirits.
In an early part of the game is a man named Torr whom the player can have low intelligence conversations with (Complete with subtitles!). The implication being that the two idiots understand one another perfectly. Here's a transcript:
Torr: Me Torr (I'm Torr. Can I help you with anything?)
Chosen One: You Torr (Hello, Torr. I do have a few questions for you.)
Torr: Torr tell? (What would you like to know, my friend?)
Chosen One: Want! (you point at things)(Where can I barter?)
Torr: Tragu? Oo Kramat? Ick boo Den. (A trader here in Klamath? Why yes, Vic trades in antiquities for the most part. He's not in town right now. I think he might be trading things at the Den. That's south of here.)
Chosen One: Bar-ba Eden? (Have you ever heard of a Garden of Eden Creation Kit?) – The clever here might note that the Chosen One just asked for Barbara Eden, or the Djinni from “I Dream of Jeannie.”
Torr: Jeannie? Gick Vic (So you want a GECK, huh? Weren't those originally issued to vaults? I don't know where you'd find one, but if anyone does it would be Vic, the trader. He specializes in prewar things. He lives in the northeast part of Klamath.)
Chosen One: Roger? Gick Vic, Haji! (Thanks; I think I'll go look for him now. Goodbye.)
Dornan: (upon being told that you were never issued your Power Armor) What was that? YOU EXPECT ME TO BELIEVE THAT, MAGGOT!? The truth is you've lost an expensive piece of army issue equipment! That suit is gonna come out of your pay! AND YOU WILL REMAIN IN THIS MAN'S ARMY UNTIL YOU ARE (inhale) FIVE-HUNDRED AND TEN YEARS OLD! WHICH IS THE NUMBER OF YEARS IT WILL TAKE FOR YOU TO REPLACE THE MARK TWO POWER COMBAT ARMOR YOU HAVE LOST!
Really, anything Dornan says. It's not really something you can express in text, though a size 72 font helps a little.
Dornan: A civilian? How in the hell did a civilian get on this base?! I'LL HAVE SOMEONES ASS FOR DINNER!
If you get too irradiated, your character sprouts a sixth toe. If you have this toe surgically removed, it's possible to eat it. The game's response? "You just ate your fucking toe!"
The conversation with Myron with a female character:
Myron: So, beautiful... how about we get in bed and do some mattress dancing?
The Chosen One: I'd love to, but I don't have 10 seconds right now. I'm out of here.
The long suffering, and very alcoholic Father Tully has many gems of wisdom to share with the Chosen One.
The Chosen One: What does Mrs. Bishop say in confession?
Father Tully: Mostly what you'd 'xpect from a neglected wifey-o with a body whoose curves could cure th' blind. Mostly adultery. I mean, have you SEEN her rack? My word!
In Fallout 2, after learning of Mob Boss Jesus Mordino:
The Chosen One: I always suspected Jesus had ties to organized crime.
Setting a timed explosive beneath the outhouse in Modoc. Due to all the methane gas down there, you go flying as you climb out (assuming you even survive), and for the remainder of the game, half the town will be covered in crap. All just to find a lost pocketwatch.
Broken Hills. The Spore Plant, which gives you information on chess against a intelligent scorpion made by the local doctor. You can take three tests against the thing: A Agility, Eye, and Smarts.
The Chosen One: How the hell did you open a lock with CLAWS?
"MOO, I say!!", says a randomly encountered brahmin. Becomes doubly hilarious when a nearby NPC will sometimes comment "I could have sworn I heard that cow shout "Moo, I say" or somesuch...."