Penny: You don't always have to go along with what the woman wants.
Leonard: Huh.
Penny: What?
Leonard: Nothing... just re-thinking my whole life

Sheldon: I need to know exactly what Leonard did to get you to put an emotional cap in his buttocks.
Penny: What?
Sheldon: Again, urban slang, in which I'm beginning to get remarkable fluency

Penny: Sheldon, what do you want?
Sheldon: I'm certain this will come as no surprise to you, but Leonard is failing in yet another relationship.
Penny: He's having problems with Stephanie?
Sheldon: She's sending virtual livestock to random men on the Internet

Penny: I am going to introduce your friend to a world of hurt.
Leonard: You don't want to get into it with Sheldon. The guy is one lab accident away from being a super villain

Penny: Wait, Sheldon. This has gotten way out of hand. Okay, I've done some stupid things; you've done some stupid things. How about we just call it even and move on with our lives?
Sheldon: I've done no stupid things.
Penny: Look, you've got to meet me half way here.
Sheldon: I am meeting you half-way. I'm willing to concede that you've done some stupid things

Leonard: Just apologize to him, okay?
Penny: What? I'm not going to apologize to that nut-case.
Leonard: Come on, it's easy. He'll even tell you what to say

Wolowitz: Over the years, we've formulated a number of theories about how he might reproduce. I'm an advocate of mitosis.
Penny: I'm sorry?
Wolowitz: I believe one day Sheldon will eat an enormous amount of Thai food and split into two Sheldons.
Leonard: On the other hand, I think Sheldon might be the larval form of his species and someday he'll spin a cocoon and emerge two months later with moth wings and an exoskeleton

Penny [after witnessing Sheldon and Ramona together]: You probably don't want to go in there.
Leonard: Why? What are they doing?
Penny: The only way I could explain it would be in a therapist's office with dolls

Sheldon: Please, please, I don't have a lot of time. Ramona finally dozed off and I need you to help me get rid of her.
Penny: Get rid of her how?
Sheldon: I don't know, but apparently I'm in some kind of relationship, and you seem to be an expert at ending them.
Penny: Excuse me?
Sheldon: I see man after man leaving this apartment, never to return.

Boy, you'd think you could trust a horde of Hungarian barbarians

Penny: What's AFK?
Sheldon: Away From Keyboard.
Penny: Oh, I see.
Sheldon: What does that stand for?

Penny: Oh, my God, a treasure chest. I'm rich!
Sheldon: Level 3 and she thinks she's rich, what a noob.

TBBT Quotes

I just gave you my virginity, woman. Cool your jets!

Sheldon

(Singing) Thor and Dr Jones, Thor and Dr. Jones. One plays with lightening, the other plays with bones.

Howard and Raj