Sheldon: If she were to log on to www.socalphysicsgroup.org/activities/other, click on upcoming events, scroll down to seminars, download the PDF schedule, and look for the seminar on molecular positroneum, well then, bippity boppity boo, our pants are metaphorically on fire.
*Leonard shuts the door.*
Sheldon: Well, sir, my trousers will not be igniting today.

Penny: What I'm saying is, Leonard might be different in a good way. And obviously, my usual choices have not worked out so well.
Sheldon: Your last choice worked out for Koothrappali. He got a free iPod.

Sheldon: Uh, One dumpling left. Who wants it?
Amy: Maybe you should offer it to the pregnant lady.
Sheldon: And that would be..?
Bernadette: Me, Sheldon. I'm obviously pregnant.
Sheldon: Well, you never said it to my face. And the last time I assumed a woman was pregnant, it did not go over well.
Penny: Yeah, I'm still mad at you.
Sheldon: You were drinking water instead of wine. What was I supposed to think?

Dr. Gablehauser: Okay, well, speaking of spreads, we're having a small welcoming party this afternoon for Mr. Kim who's agreed to join us here at the university.
Sheldon: Of course he has. The Oracle told us little Neo was the one. You can see the matrix, can't you?

Sheldon: So, this conversation is as pointless as your door knocking soliloquy?
Penny: Let me get my cockamamie keys.

Sheldon: I sense that you're trying to slow walk me to an epiphany. Would you mind very much jumping to it.

Leonard: Why don't you just tell people you're a zebra?
Sheldon: Why don't you just tell people you're one of the seven dwarves?
Leonard: Because I'm Frodo.
Sheldon: Yes, well, I'm the Doppler effect.

Sheldon: Hope you're not thinking about some sort of LSD thought control. Because there's only one mind-expanding drug this man enjoys, and that's called school.

Howard: Sheldon, there's a diploma in my office that says I have masters in engineering.
Sheldon: And you also have a note from your mother that says "I love you, Bubula" but neither of those is a cogent argument for titanium over nano-tubes.

Penny: I'll tell you what happened. (sigh) We were young. We were very much in love, but we could only communicate through a time-travelling mailbox at my lake house.
Sheldon: It's not enough that you made me watch that movie, but now you mock me with it?

Amy: What are you doing here?
Sheldon: When last we spoke, you said you needed time.
Amy: It's only been eleven hours.
Sheldon: The Lord of the Rings trilogy was nearly eleven hours. I made you watch that, you said it was an eternity.

Penny singing "Out Tonight"
Leonard: What the hell is that?
Sheldon: I don't know, but if cats could sing ... they'd hate it too.

Leonard: If you don't have any other plans, do you want to join us for Thai food and a Superman movie marathon?
Penny: A marathon? Wow, how many Superman movies are there?
Sheldon: You're kidding, right?

Raj: Here comes Kripke.
Leonard: Who's that with him?
Raj: I believe that's the president of the university.
Leonard: And the board of directors. Abort! Abort!
Sheldon: There is no abort.
Raj: How could you not put in an abort?
Sheldon: I made a boo-boo, all right?

Leonard: Do you think I'm overdressed?
Sheldon: It depends on the activity. For a prostate exam? Yes. If you're playing Vegas, I'd add sequins.