Bernadette: Sorry doesn't clean my underpants, buddy.

Penny: Oh, it's not so bad. You lost money, you're filled with shame, and you got groped by a stranger. That's Vegas. You nailed it.

Raj: What's wrong with people? Why don't they stop?
Sheldon: Maybe we're better off. What if we were to get in a car with a crazy person?
Leonard: Look at us, Sheldon. We're the crazy people!

Sheldon: Someday scientists will discover that second X chromosome contains nothing but nonsense and twaddle.

Sheldon: Excuse me. This is not about protecting my friend. Im a big fan of homeostasis. Do you know what that is?
Penny: Of course not.
Sheldon: Homeostasis refers to a systems ability to regulate its internal environment and maintain a constant condition of properties like temperature or pH.
Penny: Worst bedtime story ever!

Amy: Have I ever told you you're like a sexy praying mantis?
Sheldon: Every time you drink alcohol.

Amy: Check this out. I took the liberty of scripting a new outgoing voice mail message for both of us.
Sheldon: Hello. This is Sheldon.
Amy: And this is Amy.
Sheldon: We're not home right now.
Amy: 'cause we out dropping science, son.
Both: Leave a message.
Amy: Beep.

Sheldon: Okay, stop ruining Valentine's day and order my pizza.

Sheldon: Earlier today, I invited Professor Stephen Hawking to join me in the popular online game Words with Friends. Moments ago, he accepted my request. Do you understand what that means?
Howard: That somewhere right now Stephen Hawking is saying, "Damn it, I mean to click no."

Howard: I remember when I was five, hiding under this desk with all my Halloween candy. Had some Peanut M&Ms, went into my first anaphylactic shock and had to be rushed to the hospital. Came home, celebrated with a Snickers, went into my second anaphylactic shock.
Raj: When did you figure out you were allergic to nuts?
Howard: Sometime around the third Almond Joy.

Raj: And we're blending, and we're blending, and we're done. Sheldon: I know Mr. Data isn't supposed to smile, but here it comes. Howard: (Dressed as a Borg) Come on, guys. Let's do this. Leonard: (dressed as Captain Picard): Yeah, I'm sweating my bald cap off.

Penny: Fine, it bothers me a little. No. You know what? This is stupid. It doesn't bother me. Okay, it bothers me. But only because she wouldn't stop laughing. Leonard is not that funny.
Amy: And there you have it, prefrontal cortex reasoning versus limbic lust. If this were a boxing match, they might call it the thrilla adjacent to the amygdala. If you were a brain scientist, you would be busting a gut right now.

Mike Rostenkowski: So, why'd you agree to come?
Howard: 'Cause Bernadette made me.
Mike Rostenkowski: I tried to back out, too. My wife said I had to go.
Howard: Really? Your wife makes you do stuff? You're a big, scary cop.
Mike Rostenkowski: You're an astronaut, and your wife makes you do things, and she's only four feet tall.

Leonard: Okay, there are ogre tracks and a trail of broken candy canes in the snow. Sheldon, what do you do?
Sheldon: I signal my contempt for your cruel plan to shove Christmas joy down my throat by making a gesture that says get a load of this guy.

Raj: Wow. An end of an era.
Howard: Boy, if these walls could talk.
Leonard: They'd say, why does he touch himself so much?
Howard: Yeah.