Penny: "So instead she asked if in the future Montana ever became a state."
Amy: Hey, in the 1800s that was considered flirting.

Raj: I'm sick of people being mean on the Internet.
Howard: I think the anonymity makes everyone feel like they can say things they'd never say to your face.
Sheldon: Interesting. I can't think of a single thing I wouldn't say to someone's face.
Leonard: Never noticed that about you.

Sheldon: Professor Hawking?
Professor Hawking: Oh, brother. You should see the look on your faces.
Leonard: You really didn't like our paper?
Professor Hawking: I like your paper very much. The premise is intriguing.
Sheldon: Then why are you attacking us?
Professor Hawking: If you were sitting in a chair for forty-years, you'd get bored, too. Anyway, gotta go, I promised to help the neighbor kid with his math homework. Ciao.

Sheldon: Good to see you again, Mr. Stephen Hawking Liked Our Paper.
Leonard: Oh, and you as well, Mr. Our Premise Is Intriguing.
Howard: How do you do, Mr. I'll Admit That's Pretty Cool.
Raj: Yeah, you keep setting me up for failure.

Penny: "With a heavy heart, Amelia stood before the newly repaired time machine. She regretted giving Cooper the part he needed."
Bernadette: Because she wanted him to give her the part she needed.

Amy: Okay, that's enough.
Penny: What, no. I really want to know what happens. And Bernadette really, really, really wants to know what happens.

Leonard: You will not believe what Stephen Hawking just said.
Penny, Amy and Bernadette: Get out!

Penny: Bernadette's nickname for you is the Virgin Pina Colada.

Leonard: Your George Lucas autograph is really a me autograph.

Sheldon: Well, I've been struggling for months to come up with a theory for dark matter that doesn't make protons decay. I'm hoping to finally tackle it by optimizing my work environment. See I've got, my tea is at the perfect sipping temperature. I have fleece-lined boxer-shorts to keep my tushie toastie. And last but not least, this inspirational cat poster improved with the reassuring face of physics renegade Richard Feynman.

Penny: Have fun.
Sheldon: Oh, I will. Nothing more fun than a paradigm shifting evening of science.
Penny: (To Leonard) And you thought it was soaping me up in the shower.

Penny: I love him, but if he's broken, let's not get a new one.

Sheldon: I'm not going to work today. And would you like to know why?
Leonard: You're upset because you spent the whole night working on dark matter and didn't make a break through, and now you're worried you made a huge mistake switching fields, and you're gonna sit around and sulk all day.
Sheldon: Like a big old baby.

Sheldon: You sounded in distress. I was worried something unpleasant was happening to you, like a murder or spontaneous coitus with Leonard.

Penny: Oh, I'm just doing this awful work out. I hate it.
Sheldon: Well if you hate it, then why are you doing it? Although I could ask the same question about the coitus with Leonard.