Sorry, I replaced you with a newer model.

Sheldon: No, go ahead, say it. I know what it is. I've heard it my whole life. The word's "annoying." Go ahead, say it. Say it. Say I'm annoying.
Amy: Sheldon...
Sheldon: Oh, it won't hurt my feelings. Go ahead, Amy, say I'm annoying. I'm annoying. I'm annoying. I'm annoying.

And, not just on the cheek. On the mouth ... like mommies and daddies do.

Leonard: Buddy, I don't think you can. I mean, once it's out there, it's out there. This thing is like the science equivalent of a sex tape.
Sheldon: You know, frankly, I'd prefer a sex tape.
Leonard: You don't know what a sex tape is, do you?
Sheldon: No.

Amy: So you just got lucky?
Sheldon: Sheldon Cooper doesn't get lucky.
Amy: You and me both.

I feel like my mind just made a baby. And, it's beautiful. It's not like human babies which are loud and covered in goop.

Amy: Sheldon, you're not a weirdo.
Sheldon: I wasn't speaking about me.

Oh, please. I'm your boyfriend. You call me Sheldon. That's right. I'm in a relationship with this cute little lump of wool. It's a physical relationship, too. Hand-holding, hugging ... even on hot days.

Ah, Sweden. Yeah, home of my favorite Muppet and, uh, second favorite meatball.

Sheldon: You sure your mothlike personality won't be drawn to this blazing fire that is myself?
Amy: More and more sure.

Don't be insulted. He just thinks too much of you would be mind-numbingly tedious.

Howard: Wait. Wait. If it wasn't for Indiana Jones, the ark would never have ended up at the warehouse!
Sheldon: (gasps) That's true! He collected and delivered the ark to the proper authorities for filing.
Raj: Like a hero.
All: Yeah! Right! Yes!
Leonard: Although, technically, Indy was supposed to take the ark to a museum to be studied. He couldn't even get that done.
All: Aww.

TBBT Quotes

Oh, Bernadette, please play my clarinet.

Raj's poem

Sheldon: I'll have a diet Coke.
Penny: Can you please order a cocktail? I need to practice mixing drinks.
Sheldon: Fine... I'll have a virgin Cuba Libre.
Penny: That's... rum and Coke without the rum.
Sheldon: Yes, and would you make it diet?