Sheldon: I'm not good with cold, Leonard. How often have we had to leave a movie theater because I got a headache from drinking the Icee too fast? I can't go.

Leonard: Sheldon, what are the words I can say right now to end this conversation and let me go back to sleep?
Sheldon: Odd, President Siebert posed the exact same question.
Leonard: How was it resolved?
Sheldon: It wasn't. His wife set the dogs on me, and rendered the question moot.

Mrs. Koothrappali: So, she has no problem with her son being eaten by a walrus?
Sheldon: That's very unlikely, Mrs. Koothrappali. If Raj dies, it'll be from frostbite, gangrene, acute sunburn or being ripped to shreds by a hundred pound polar bear.

Leonard: "Leonard, call me if you're interested in coitus. Sincerely, Maggie McGeary."
Sheldon: And if anyone were to actually call that number, they will hear this: "Top of the mornin' to you. You've reached Maggie McGeary. Leave a message after the wee little beep."

Sheldon: And here is the clincher, a lock of Maggie's flaming auburn hair.
Leonard: Where did you get that?
Sheldon: From an orangutan in the primate lab.
Leonard: An orangutan?
Sheldon: Well, no one's going to run a DNA test on it, Leonard. Honestly, you over think everything.

Sheldon: Rut? I think you mean consistency. And if we're going to abandon that, then why even call it Thursday? Let's call it Quonko Day and divide it into 29 hours of 17 minutes apiece, and celebrate it by sacrificing a goat to the might god Ra.

Penny: While you're there, could you pick up a few comics for my nephew's birthday?
Sheldon: I think you mean comic books. Comics are feeble attempts at humor featuring talking babies and anthropomorphizing pets found traditionally in the optimistically named funny pages.

Sheldon: Look at that, that's a dent. Thank you, Howard ham-fisted Wolowitz.

Leonard: Why would you want a glow-in-the-dark ant farm?
Sheldon: They do some of their best work at night.

Sheldon: All right, I see what's going on. This is the opening salvo in what will be an escalating series of juvenile tit-for-tat exchanges. Well titted.
Raj: Thank you.
Sheldon:Stand by for my upcoming tat.

Penny: Ooh, I thought I smelled pizza.
Sheldon: That's remarkable. If pepperoni were an explosive substance, you could replace German shepherds at our nation's airports.

Penny: Today I drove to Van Nuys for an audition I thought was going to be for a cat food commercial. Turned out to be for porn.
Sheldon: Did you get the part?
Penny: I didn't do the audition.
Sheldon: Given the state of your career, can you really afford to be picky?

Penny: Kite fighting?
Leonard: Oh, yeah. It's an extremely competitive, cutthroat sport.
Sheldon: Well, actually, the risk of throat cutting is very low. On the other hand, severe string burn is a real and ever-present danger.

Leonard: Maybe Koothrappali's right. Maybe I embarrass her.
Sheldon: You're embarrassing me right now. A grown man worrying about such nonsense when in the middle of flying kites.

Sheldon: That's exactly what my father said. Come to the games, watch the games, week in and week out from the time I was five until I went off to college. Longest seven years of my life.