Penny: Who's Adam West?
Sheldon: Who's Adam West!? Leonard, what do the two of you talk about after the coitus?

Sheldon: My new computer came with Windows 7. Windows 7 is much more user-friendly than Windows Vista. I don't like that.

Sheldon: As a native Texan, I must say I've never heard the phrase "yeeehaw" used in quite that context.

Penny: I think I caught the flu. *Throwing up*. Or the plague!

Penny: Hey Sheldon, whattcha got there a new comic book?
Sheldon: Old comic book. I just got it from the safe deposit box.
Penny: What do you have a safe deposit box for?
Sheldon: Old comic books.

Leonard: A long time ago, I made a deal with Howard involving you.
Penny: Okay, I don't know where this is going, but tread carefully, because this may be the last conversation we ever have.

Sheldon: Hello, Kripke. This classic prank comes to you from the malevolent mind of Sheldon Cooper. If you would like to see the look on your stupid face, this video is being instantly uploaded to YouTube. Oh, and a hat tip to Leonard Hofstadter and Raj Koothrappali for their support and encouragement in this enterprise.

Sheldon: Tweet that, tweetie bird.

Sheldon: Hello, Amy Farrah Fowler. I'm sorry to inform you that you've been taken in by unsupportable mathematics designed to prey upon the gullible and the lonely. Additionally, I am being blackmailed with a hidden dirty sock.
Amy: If that was slang, I'm unfamiliar with it. If it was literal, I share your aversion to soiled hosiery.

Sheldon: No mother, I could not feel your church group praying for my safety. The fact that I am home safe does not prove it worked. That logic is post hoc ergo propter hoc. No, I'm not sassing you in Eskimo talk.

Sheldon: What are you talking about?
Leonard: The cultural paradigm in which people have sex after 3 dates.
Sheldon: I see. Now, are we talking date the social interaction or date the dried fruit?

Penny: So, how've you been?
Sheldon: Well, my existence is a continuum, so I've been what I am at each point in the implied time period.

Leonard: Uh, sleep night. I mean, obviously, good night. I started to say sleep tight then I changed my mind in the middle. I swear to God, I'm smart.
Sheldon: Get it together, man.

Sheldon: (To a policeman) They took our TV, two laptops, four external hard-drives, our PS2, our PS3, our X-Box, our X-Box 360, our classic Nintendo, our Super Nintendo, our Nintendo 64 and our Wii.
Leonard: We like games.
Sheldon: Right, games. They took Halo 1, Halo 2, Halo 3, Call of Duty 1, Call of Duty 2, Call of Duty 3, Rock Band, Rock Band 2, Final Fantasy 1 thru 9, The Legend of Zelda, The Legend of Zelda: Ocarina of Time, The Legend of Zelda: Twilight Princess, Super Mario Brothers, Super Mario Galaxy, Mario and Sonic at the Winter Olympics and Ms. Pacman.
Policeman: (Writing down) Assorted video games.

Sheldon: Would you like me to bring you some warm milk?
Leonard: I'm lactose intolerant.
Sheldon: And you don't wish to alarm me with any more loud noises. Very thoughtful.