Amy: You realize none of those things would happen now?
Sheldon: I do, but why do you care if I celebrate my birthday at all?
Amy: Well, you made my last birthday so memorable, I wanted to return the favor.

Amy: Okay, what is going on?
Penny: We just want you to be prepared for any surprises that could happen tomorrow.
Amy: What surprises?
Bernadette: We don't want to spoil anything, but you should know that Sheldon said he's ready to be physical.
Amy: You shut your damn mouth! You actually heard him say this?
Penny: Yes, he said he wants to do something to show you how much you mean to him.
Amy: I can't believe it. I don't know what to say.
Bernadette: Well, we're really happy for you and we know how much-
Amy: I do know what to say. Let's get me waxed!

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?

Amy: Do you have any idea how hard it is to laugh at a knock knock joke that starts "Knock Knock Knock, Amy. Knock Knock Knock, Amy. Knock Knock Knock, Amy"?

Penny: So what's going on?
Sheldon: I don't know. I looked around the room, and I saw all the faces and the presents, and it it was just too much.
Penny: I get that. Hey, you want to just bring a few people in here? You know, Wil Wheaton in the bathtub, Batman on the toilet. It'll be like the weirdest Comic-Con ever.

Leslie Winkle: Uh, in the past, I would've said something obnoxious, like, "Happy birthday, dumbass". But I'm not gonna do it. You and I have both grown a lot, and it's just so nice to see you all again. So happy birthday, Sheldon.
Sheldon: Oh. Oh, now, you know I hate change. Say it.
Leslie Winkle: Happy birthday, dumbass!

Amy: We've got someone who couldn't be here but really wanted to wish you a happy birthday.
Stephen Hawking: Hello, Sheldon.
Sheldon: (gasps) Professor Hawking.
Stephen Hawking: Happy birthday to you.
Sheldon: Thank you so much. I can't believe you're-
Stephen Hawking: Happy birthday to you.
Sheldon: Oh, you're singing. Well, I'm sorry.
Stephen Hawking: Happy birthday, dear Sheldon.
Leonard: Uh, Professor Hawking, if you just give us one second, we'll light the candles, and we can all sing together.
Stephen Hawking: I was crushing it, but all right.