Sheldon: Please. We're facing a far more serious problem than stray arachnids.
Leonard: It's not so bad.
Sheldon: Not bad? It's horrible. You hear stories about this things, but you never think it'll happen to you.
Leonard:So they steamed your dumplings. Get over it.

Sheldon: "Barney Bunny has two daddies now." Probably something about homosexual rabbits.

Penny: So, do you think that if Leonard and I keep dating, Leonard would get bored with me?
Sheldon: That depends.
Penny: On what?
Sheldon: Do you have a working knowledge on Quantum Physics?
Penny: No.
Sheldon: Do you speak Klingon?
Penny: No.
Sheldon: Do you know any card tricks?

Penny: Get them down!
Sheldon: Apologize.
Penny: Never.
Sheldon: Then you just get a very long stick and play panty pinata!

Sheldon: *On computer screen* Greetings, hamburger toucher. You are probably wondering why you cannot IM with your little friends about how much you heart various things. Well, this recorded message is alerting you that I am putting an end to your parasitic piggybacking upon our WiFi. If you want to remedy the situation you can contact the phone company, set up your own WiFi and pay for it, or you may apologize to me.

Leonard: Hey, Sheldon, are you coming?
Sheldon: I'd rather have a blowfly lay eggs and hatch larvae in my auditory canal.

Penny: What about Howard and Raj? How did he become friends with them?
Leonard: I dunno. How do carbon atoms form a benzene ring? Proximity and valence electrons.
Penny: Sure, when you put it like that.

Wolowitz: According to Alicia's Facebook page, she's hooking up with one of the producers on CSI.
Penny: Dead whore on TV, live one in real life.

Howard: Are you familiar with the Drake Equation?
Sheldon: The one that estimates the odds of making contact with extraterrestrials by calculating the product of an increasingly restrictive series of fractional values such as those stars with planets, and those planets likely to develop life? N equals R times FP times NE times FL times FI times FC times L?
[pause]
Howard: Yeah, that one.

Penny: What was my first strike?
Sheldon: March 18th, you violated my rule about forwarding email humor.
Penny: I did?
Sheldon: The photo of the cat who wants to "Has Cheeseburger?"
Penny: Oh, come on, everybody loves Lolcats. They're cute and they can't spell because they're cats.
Sheldon: I trusted you with my email address and you betrayed that trust by sending me internet banality. Strike one. Touching my food. Strike two.

Sheldon: Your check-engine light is on.
Penny: Uh huh.
Sheldon: Typically, that's an indicator to, you know, check your engine.
Penny: It's fine. It's been on for like a month.
Sheldon: Well, actually that would be all the more reason to, you know, check your engine.
Penny: Sheldon, it's fine.
Sheldon: If it were fine, the light wouldn't be on. That's why the manufacturer installed that light, to let you know it's not fine.
Penny: Maybe the light's broken.
Sheldon: Is there a check-the-check-engine-light light?

Sheldon: And you thought the opposite of stupid loser was a Community College Graduate?

Dr. Gablehauser: What colorful nickname did you call Dr. Cooper this time?
Leslie: Dr. Dumbass.

Sheldon: You know, it's amazing how many super villains have advanced degrees. Graduate schools should do a better job of screening those people out.

Penny: Leonard, look. Sheldon's hugging me!
Leonard: It's a Saturnalia miracle.