Raj: Amy, good luck getting these guys excited about a dinner with a theme. I gave up when no one cared about my Tom Hanks-Giving.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Bernadette: You better find my husband's mother, 'cause one way or another we're walking out of this airport with a dead woman.

Sheldon: May I say something?
Leonard: Not right now, Sheldon.
Sheldon: But I think it may be comforting.
Leonard: Buddy-
Howard: No, it's okay. What?
Sheldon: When I lost my own father, I didn't have any friends to help me through it. You do.

Leonard: What am I supposed to do?
Penny: Err, keep your mouth off other women.

Sheldon: I know the real reason you never made progress with that idea. You thought of it September 22nd, 2007. Two days later, Penny moved in and so much blood rushed to your genitals, your brain became a ghost town.

Howard: I'm sorry I didn't take you to the airport. I just want you to know I'll never forgive myself for being so selfish. And I promise to keep you close for the rest of my life.
Bernadette: Oh, no, that thing's gonna end up in my bedroom.

Sheldon: It reminds me of when my stupid brother and sister would build forts in the living room, and wouldn't let me in. I hated that so much.
Amy: You know, there's nothing I can do about getting you invited to the symposium, but if you wanted we could build a fort.
Sheldon: Isn't that a little juvenile?
Amy: More juvenile than this? *Puts up picture of smiling Sheldon to her face*

Amy: But enough about Penny, let's talk about us. We're looking good.
Bernadette: We are.
Amy: Better than good. I mean look at you, your body's bangin'.
Bernadette: Amy!
Amy: Don't Amy me. We're always talking about how hot Penny is. Come on, scientist to scientist, how big are those hadron colliders?

Sheldon: I really did think you looked pretty.
Amy: You did?
Sheldon: Yes. So much so that I started to panic.
Amy: Well you can relax. Just because you think I look pretty doesn't mean we have to spend the night together.
Sheldon: Were you hoping we would because it's prom?
Amy: I'm always hoping. But tonight, I just wanted to have a nice time with you. Maybe dance with someone who has arms.

Josh: So, I have to ask, was the robot sexy?
Howard: It was actually just a mechanical hand.
Josh: 'Cause that's all you need, right?
Howard: You are my brother.

Bernadette: She's just being nice.
Howard: Well, I'm her son, how come she doesn't send someone to check on me if I'm lonely.
Bernadette: Because you have a wife!
Howard: Yeah, well, sometimes you work late.

Penny: At one point, they had me figure out how to get a banana out of a puzzle box.
Leonard: Wait, Sheldon gave me a banana in a box. He was testing me, too.
Penny: Unbelievable.
Leonard: And how could a chimp even solve that? That was impossible.
Penny: Really? You couldn't get it out?

Penny: Sheldon, we know this is a sensitive subject, and Leonard's not going to move out until you're ready.
Sheldon: What if you did it gradually?
Leonard: All right, how about we start with two nights a week I live with Penny?
Sheldon: How about one night and I let you whistle?
Leonard: Okay.
Sheldon: When I'm not home.

Sheldon: Thank you for understanding.
Amy: Of course I understand. Sheldon, there's something else I've been wanting to say, but before I do, I just. I want you to know you don't have to say it back. I know you're not ready and I don't want you to say it just because social convention dictates -
Sheldon: I love you, too.
Amy: You said it.