Amy: You are aware that your ritualistic knocking behavior is symptomatic of obsessive-compulsive disorder?
Sheldon: Is not. Is not. Is not.
Amy: Denial. Denial. Denial.

(Howard has just told Mary about his upcoming trip to the International Space Station.)
Mary Cooper: I bet your mom is really proud of you.
Howard: Nope. She says if I don't back out, she's gonna go on a hunger strike. It'd take years before she'd be in any kind of danger, but still.

Amy: If you're keeping him, I've got a cage you can borrow. One of the test monkeys slipped on a banana peel and broke his neck. It was both tragic and hysterical.

Penny: So you're saying if I became a famous movie star, we got married, you wouldn't sign a pre-nup?
Leonard: Absolutely not! If I'm gonna be stuck at home with the kids while you're on location cheating on me with Ryan Gosling, then Leonard gots to get paid.

Raj: But excuse me, I have something to say. None of you may realize it, but I was very much looking forward to this weekend. It was gonna be like the old days -- the four of us hanging out, playing video games, before you guys all got girlfriends. Do you have any idea what it's like to be the only one without a girlfriend? Even if I get one someday, I'll still be the guy who got a girl after Sheldon Cooper!

Penny: Hey, what are you guys doing here?
Howard: We're grown men, we drink at bars.
Penny: No and no. Everything okay with you and Bernadette?
Howard: Oh yeah, sure.
Penny: You and Amy? Good?
Sheldon: Oh, better than good.
Penny: You know those girls text me every detail of their lives as it happens.

Mrs. Wolowitz It's this dress. When I put my front in, my back pops out. When I put my back in, my front pops out. It's like trying to keep two dogs in a bathtub.
Sheldon: What do you want me to do?
Mrs. Wolowitz We're gonna have to work as a team. Get in here, grab a handful and start stuffing.

Leonard: If you're worried, we can go over there and see if she's all right.
Sheldon: Okay. You know, I heard in the news a bobcat has been spotted in her neighborhood.
Leonard: I don't think Amy was eaten by a bobcat.
Sheldon: Who thinks Amy was eaten by a bobcat?
Leonard: You do?
Sheldon: Leonard, I was just mentioning an interesting local news item. Now, thanks to you, I'm worried Amy's been eaten by a bobcat.

Mary Cooper: It's all themed. There's Jonah and the Whale Watching. All-you-can-eat Last Supper Buffet. And my personal favorite, Gunning with God.

Bernadette: Boy, I don't know if I could be friends with Howie if we broke up.
Howard: Why not?
Bernadette: I'm a very vengeful person.
Howard: Really?
Bernadette: With access to weaponized smallpox.

Sheldon: The entrance to the dungeon is a moss covered door. You manage to open it only to find yourself face-to-face with a hideous, foul-smelling, moss-covered ogre. What do you do?
Howard: I say, "Hey Ma, what's for dinner?"

Sheldon: For the record, I do have genitals. They're functional and aesthetically pleasing.

Sheldon: I believe I would like to alter the paradigm of our relationship.
Amy: I'm listening.
Sheldon: With the understanding that nothing changes what so ever - physical or otherwise, I would not object to us no longer characterizing you as not my girlfriend.
Amy: Interesting, now try it without the quadruple negative.

Leonard: You call that a glow stick? *Pulls out a Lightsaber* That is a glow stick!

Amy: A guest in my trundle bed and a boy at my door. I wish I could tell thirteen-year-old me it does get better.