Leonard: The elevator's been broken for two years.
Sheldon: I've been meaning to ask you. Do you think we should make a call about that?
Wolowitz: Not necessary. I have a Masters in Engineering. I remotely repair satellites in a regular basis. I troubleshoot space shuttle payloads. When the Mars Rover started pulling to the left I performed a front-end alignment from 62 million miles away. [pushes the button...] No, that baby's broken

Leonard: Come on, guys, push!
Howard: If I push any harder I'm gonna give birth to my colon.
Raj: I can't feel my fingers. Hurry up!
Sheldon: It's the same amount of work no matter how fast you go—basic physics.
Raj: Sheldon, if my fingers ever work again, I've got a job for the middle one

Sheldon: Why'd you set it for the day before yesterday?
Leonard: Because I want to go back and keep myself from getting a time machine.
Sheldon: You can't. If you were to prevent yourself from buying it in the past, you would not have it available in the present - travel back and stop yourself from buying it, ergo you would still have it. This is a classic rookie time travel mistake.
Leonard: Can I go back and prevent you from explaining that to me?
Sheldon: Same paradox—if you were to travel back in time and, say, knock me unconscious, you would not then have the conversation that irritated you, motivating you to go back and knock me unconscious.
Leonard: What if I knocked you unconscious right now?

Raj: Too bad, I called dibs.
Wolowitz: You can't just call dibs.
Raj: I can, and I did. Look up "dibs" in Wikipedia.
Sheldon: Dibs does not apply in a bidding war

Leslie: Hello, Sheldon.
Sheldon: Leslie Winkle!
Leslie: Yeah, Leslie Winkle! The answer to the question, "Who made Sheldon Cooper cry like a little girl?"
Sheldon: Yes! Well, I'm polarized tree sap and you're inorganic adhesive, so whatever verbal projectile you launch in my direction it's reflected off of me, returns on its original trajectory and adheres to you

Penny: What actor holds the record for being named People magazine's Sexiest Man Alive?
Sheldon: William Shatner!
Leonard: I don't think it's Shatner.
Sheldon: Then it's got to be Patrick Stewart

Wolowitz: Don't you think I should answer the engineering question? I am an engineer.
Sheldon: By that logic I should answer all the anthropology questions because I'm a mammal

Sheldon: Count me out.
Leonard: What? ...why?
Sheldon: You want me to use my intelligence in a tawdry competition. Would you ask Picasso to play Pictionary? Would you ask Noah Webster to play Boggle? Would you ask Jacques Cousteau to play Go Fish?

Leonard: Sheldon, you have to let somebody else answer.
Sheldon: Why?
Penny: Because it's polite.
Sheldon: What do manners have to do with it? This is war. Were the Romans polite when they salted the ground of Carthage to make sure nothing would ever grow again?

Sheldon: I've designed the perfect uniforms for our team. The colors are based on Star Trek: The Original Series; the three of you will wear support red, and I will wear command gold.
Leonard: Why do they say, "AA"?
Sheldon: Army Ants.
Leonard: Isn't that confusing? AA might mean something else to certain people.
Sheldon: Why would a Physics Bowl team be called Anodized Aluminum?

Sheldon: Point of order. I move that any vote on team names must be unanimous. No man should be forced to emblazon his chest with a Bengal tiger when common sense dictates it should be an army ant.
Leonard: Will the gentleman of the great state of denial yield for a question?
Sheldon: I will yield.
Leonard: After we go through the exercise of an annoying series of votes, all of witch the gentleman will lose, does he then intend to threaten to quit if he does not get his way?
Sheldon: He does!
Leonard: I move we are the Army Ants

Leonard: Check it out. I got you a Batman cookie jar.
Sheldon: Ohhh, neat, what is the occasion?
Leonard: Well, you are a friend, and you like Batman and cookies, and you are off the team

TBBT Quotes

Penny: Here's a question-- as an alien pretending to be human, are you planning to engage in any post-prom mating rituals with Amy?
Sheldon: There are post-prom mating rituals?
Penny: Not always. Unless your date drives a van with an air mattress, then always.
Sheldon: Well, if it's part of the prom experience, then I'm open to it.
Penny: You're kidding.
Sheldon: I may be an alien, but I have urges.If Amy wants to copulate by firing her eggs into space, well, then, I will happily catch them with the reproductive sac on my upper flermin. I'm not the best at reading facial cues, but I can see that you're a little turned on.

Penny: Hey, Sheldon, did you change your Wi-Fi password again?
Sheldon: Yes, it's "Penny, get your own Wi-Fi." No spaces.