Sheldon: You would never make me kiss you, then say I love you, then break up with me.
Leonard: I wouldn't.
Sheldon: You know why? Because you're a man. The champagne of genders.
Leonard: I may be a man, but I think I'm the one that screwed up on this one.
Sheldon: And you admit it. Like a man. All your hear woman say is "I'll have a salad", "Where's my lip gloss?", "I think this element should be called radium."
That last one was Madame Curie.
Leonard: I figured that out.
Sheldon: You know what? She was sort of an honorary man. She had a penis made of science.

Sheldon: But enough about the Czech Republic. Let's talk about the time Moldova made Romania a birthday cake, and Romania said it tasted good even though it didn't, and yet Romania got dumped. I'll pause here while you mull that one over. I know, right?

Raj: Yeah, okay, whatever it takes to keep you busy for a few hours.
Sheldon: Found one.
Raj: No, you didn't. There are millions of data points there.
Sheldon: But, look, an optical transient.
Raj: Yeah, maybe that is something. How did you find that?
Sheldon: It wasn't difficult. You know how when you see prime numbers, they appear red, but when they're twin primes, they're pink and smell like gasoline?
Raj: No.
Sheldon: Oh. I guess I'm a special boy. You know, sometimes when a boy is special, he gets a Fudgsicle. Which, by the way, tastes like the speed of light.

Amy: Listen, you and I are gonna be sharing a bed. You know, this is uncharted territory for both of us. How are you feeling about that?
Sheldon: Oh, excited, concerned, a little scared. All the same emotions I feel in line at Space Mountain.

Sheldon: If you want to blend in with Penny's friends, I'd think looking like an idiot would be the perfect camouflage.

Leonard: How long is he going to stay here?
Sheldon: He's a homeless drug addict, Leonard. Where's he going to go? Boy, you have a lot to learn about lying.

Sheldon: Are you implying my girlfriend doesn't have any sexuality to exploit?
Raj: Yes.
Sheldon: Okay, because that was not clear.

Sheldon: That's curious. If there's no one here, why are there two glasses of wine on the table?
Penny: Oh, well you know. I've got two hands and a bit of a drinking prolbem.
Sheldon: Of course. Ask a silly question.

Amy: When you told me I was going to be "losing my virginity", I didn't think you meant showing me Raiders of the Lost Ark for the first time.
Sheldon: My apologies. I chose my words poorly. I should have said you were about to have your world rocked on my couch.

Sheldon: Amy's sick.
Leonard: Aww, what's wrong with her?
Sheldon: Well, she talks a lot. Always wants to hold hands.
Leonard: That's not what I meant.
Sheldon: Well, if you were referring to her illness, your question should have been "What ails her?"
Leonard: What ails her?
Sheldon: Oh, who knows.

Sheldon: Wow, wow, wow, wow. Just because I love you, doesn't mean girls are allowed in my room.

Amy: Okay. Anyway, um, it's nice to see you. You look good.
Sheldon: Thanks. And I taste good too.

Sheldon: Five minutes? We must be doing it wrong. It took us hours.

Sheldon: And just remember, I am proud of you and I support you in all that you do.
Amy: Thank you. That means a lot.
Sheldon: Oh, and one last thing. If you find yourself working with a male scientist who's as smart as me, as tall as me and has hair like Thor, well, then I want you to step away from the situation and call me immediately.

Penny: What if you asked for $20 million?
Sheldon: I'm sorry, I'm trying to do science, not hire Lady Gaga to come to my birthday.
Penny: Do you even know who Lady Gaga is?
Sheldon: Presumably, the wife of Lord Gaga.