Penny: Oh, my God, he won't stop.
Leonard: How does he keep coming up with new ways to be annoying?
Penny: Nobody knows. That's why he's number one.

Amy: Whose bra is this?
Sheldon: It's not yours? Oh, my. How embarrassing for both of us.
Amy: It's Penny's.
Sheldon: Hey. You broke up with me, it's none of your business whose naked bosom I'm smushing around like pizza dough.

Raj: You're not wrong about Fruit Stripe. I-I was always a Hubba Bubba man.
Howard: Hubba Bubba over Dubble Bubble? You're crazy.
Raj: Hey, the jaw wants what it wants.

Wil Wheaton: Hey, Sheldon. This is Adam Nimoy.
Adam Nimoy: Nice to meet you.
Sheldon: Oh, it's nice to meet you. I admire your father's work very much.
It's not every day I get to meet someone whose life's journey began in my hero's scrotum.

Leonard: Guys, tickets already went on sale.
Sheldon: What?
Howard: They're not supposed to be available yet.
Leonard: I don't know what to tell you, but they're already available.
Raj: Wait, are you sure they're Star Wars tickets?
Leonard: No, it's Steel Magnolias 2: Even Steelier.

Stuart: Anyone else need anything before I go?
Howard: I'll give you a dollar if you make fun of Raj.
Stuart: That's mean.
Howard: Five.
Stuart: You look like Tigger if Tigger looked like a jackass.
Howard: Uh, if you ever need a reference or anything, just let me know.

Sheldon: I don't think I can go back out there.
Penny: That's fine. You know, I hate that your sister and her friends used to torture you. But what I hate even more is, if I was there, I would have tortured you, too.
Sheldon: Based on this pep talk, I'd say you're still doing it.
Penny: My point is, there was a time I never would've been friends with someone like you, and now you are one of my favorite people. So, if what you need is to spend your birthday in a bathroom, I'm happy to do it with you.
Sheldon: Well, everyone will think I'm weird.
Penny: Sweetie, you are weird. Everyone knows you're weird, but they're all still here because they care about you so much.

Sheldon: Dear Crazy Future Sheldon, you were driven mad by an earworm. Your mind, once your most trusted asset, is now a sack of parrots and monkeys. So I'm going to tell you everything you need to know. Uh, first, music is dangerous. The movie Footloose tried to warn us, but we wouldn't listen.

Raj: I can't believe Sheldon gave this up.
Leonard: I know. We're gonna have so much more fun than him.
Bernadette: No, they're not.
Penny: Knowing them, they will.

Sheldon: (3 knocks) Birthday girl! (3 knocks) Birthday girl! (3 knocks) Birthday girl!

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.

Raj: Come on, a medium-sized asteroid is still an interesting discovery.
Sheldon: I suppose it could end up on a collision course with Earth and destroy life as we know it.
Raj: You dream different than me.

Raj: My name is Little Orphan Annie. You killed my father. Prepare to die.
Howard: My name is Darth Vader. I am your father. Prepare to die.

Amy: That's Sheldon.
Dave: You're kidding! How's my hair?

Amy: If you don't mind me asking, why did you and your wife split up?
Dave: Oh, you know how it is. We wanted different things. I wanted children, and she wanted a pastry chef named Jean-Philippe.