Bernadette: How many times has he made fun of Howard for being an engineer? Going to MIT? His magic?
Amy: Sheldon doesn't make fun of his magic.
Bernadette: Well, he should. It's stupid.

Amy: You know, these experiments are pretty harmless. There's one where you just put the baby in front of a mirror and you watch them watch themselves.
Raj: That sounds adorable. Let me see.
Sheldon: How come when she talks about experiments on babies, you think it's adorable, but when I do it, everyone gets upset?
Leonard: I think I can speak for all of us. You're just creepy.
Howard: No offense.

Leonard: Hey, do you remember what happened at that first Halloween party that you invited me to?
Penny: When I threw up in the pumpkin?
Leonard: More memorable than that.
Penny: Really? That was pretty impressive.
Leonard: We had our first kiss. On this very couch.
Penny: No, no, our first kiss was at your birthday. Remember? I threw you a party, you didn't make it, and I felt bad for you.
Leonard: No, no, it was on Halloween, and you felt bad for me.
Penny: If we're gonna go through every party where I felt bad for you, we're gonna be here awhile.

Sheldon: I will admit the meeting did not go the way I wanted.
Howard: [imitating Shatner] Because you barfed where no man has barfed before?

Sheldon: It's a congratulations text from my meemaw. [phone vibrates] Ooh. Oh, and there's one from my mom. [phone vibrates] And my sister. [phone vibrates] Oh, and my brother. [phone vibrates] And my brother's ex-wife. [phone vibrates] My brother's other ex-wife. Boy, they don't tell you when you win a Nobel it chews up your phone battery.

Penny: Wow, she's being really nice.
Leonard: Yeah, clearly, one of us is dying. Come on, her.

Sheldon: Well done. You know, you're proving to be an invaluable part of my entourage.
Leonard: Cool.

Amy: Are you guys all dressing up for work?
Howard: Of course. I mean, how often do you get to wear costumes to work?
Penny: Says the man with a giant belt buckle and a dickey.
Howard: Hey, this is not a costume. It's a choice. It's a style.
Penny: It's a tragedy.

Raj: How's the concierge conference? You guys just get theater tickets for each other all day long?
Anu:It's going great, and the company put me in a nice place in Notting Hill.
Raj: Notting Hill? Like the movie? Uh, "I'm just a boy standing in front of a girl saying" you better bring me home a T-shirt.

Sheldon: Also, if you get a chance to sneak into Hall H, last year, I left my neck pillow under my seat. Uh, third row, second from the aisle.
Penny: I'll see what I can do.
Sheldon: Thank you. At least there will be one superhero in San Diego.

Howard: Hello. [dressed like Sheldon, imitating him]
Sheldon: Hello.
Howard: I see you are dressed as Doc Brown from Back to the Future. May I assume that Amy is going as his wife, Clara Clayton, from Back to the Future Part III?
Sheldon: She is. Did you do something different to your hair?
Howard: Yes.
Sheldon: Looking good.

Sheldon: Uh, don't worry, Leonard, you're still my California best friend.
Leonard: Cool.
Sheldon: So, what do you want to do now? Go to the train store, go to the comic book store?
Tam: Actually, I have to grab my son and head to the airport. I was just about to call a cab.
Sheldon: Don't be silly, you don't have to call a cab. You're my oldest friend. Leonard will take you. Right, Leonard?
Leonard: Sure.

Sheldon: You just remember the mnemonic: if it's number one, the library's fun, if it's number two, the basement's for you.

Beverly Hofstadter: Really? A photon entanglement team.
Leonard: Yeah, I'm actually the colead.
Penny: Yeah, if you like photons and how they get entangled, he's your co-guy.

Bernadette: We have kids, and it's not smart to put us both in danger.
Raj: That's a good point. When I was little, my parents never flew together. We thought it was because they loved us, but it turns out they hated each other.