Sheldon: Leonard, you're my best friend. Why don't you ever take my side.
Leonard: Because I can never understand your side!

We're still dating, right?

Leonard: Who you talking to?
Penny: Just this guy I met at school.
Leonard: We're still dating, right?

Howard: Boy, if these walls could talk.
Leonard: They'd say, "Why does he touch himself so much?"
Howard: Yeah.

She writes like she cooks.

Sheldon: Oh, ow, blueberry in my nose. Blueberry in my nose.
Leonard: Snort it down and keep eating.
Sheldon: [snorts]

Sheldon: How could you not find him?
Leonard: Because he's hard to find. If he was easy to find, the books would be called "There's Waldo."

A solar system? Uh,uh,um, unidentified flying liverwurst? I don't....

Leonard: In what universe is that a present?
Sheldon: It's not a present. It's the present. There's you and me. It's Penny and Amy. We're playing Pictionary. In the present.

It had weaponized fruit and a puppet. What more do you want?

Mmm, the nurse is a woman, so he couldn't talk to her. She had to bring him a Grover puppet so he could point at what hurt.

Leonard: The guy who seems like an emotionless robot ... is you, but your relationship with Amy is causing you to transform into a red-blooded man with sexual desires.
Sheldon: That is literally the stupidest thing I've heard.

TBBT Quotes

Sheldon: Are you still mad about the sperm bank?
Leonard: No!
Sheldon: Do you want to hear an interesting thing about stairs?
Leonard: Not really.
Sheldon: If the height of a single step is off by as little as two millimeters most people will trip.
Leonard: I don't care—two millimeters?! That doesn't seem right.
Sheldon: No, it's true! I did a series of experiments when I was twelve; my father broke his clavicle.

Penny, there's only one cookie with something in the middle that solves life's problems, and that's an Oreo. Or a Nutter Butter, if you're in a pinch.

Sheldon