Howard: Why is it taking him so long to get a drink out of a vending machine?
Leonard: Oh, it's complicated. He finds pushing that little door and reaching up into the machine uncomfortably intimate.

Sheldon: I remember the song! It's called "Darlin'" by the Beach Boys! Oh, thank goodness! I'm not crazy! I don't have to take a pigeon as my bride!
Leonard: There goes our shot at him living on the roof.

Howard: Don't feel bad. Some day someone will be throwing out your work, too.
Leonard: That someone was Sheldon and the day was yesterday.

Professor Proton: Can I ask you a question?
Leonard: Yeah, sure.
Professor Proton: Why do you put up with Sheldon?
Leonard: Oh, you know because we're friends.
Professor Proton: Why?
Leonard: Wow, you ask really hard questions. Look, I know he can be aggravating, but what you have to remember is he's not doing it on purpose, it's just how he is. But he's also loyal and trustworthy and we have fun together.
Professor Proton: You know you're describing a dog?
Leonard: He did bite me once. But in his defense, I came up behind him while he was eating.
Professor Proton: They hate that.
Leonard: Sheldon is the smartest person I have met. He's a little broken and he needs me. And I guess I need him too.
Professor Proton: Why is that?
Leonard: Boy, you will not let this go, will you?

Sheldon: No, I know, but plenty of things are addictive after a single exposure. I mean, crack cocaine, nicotine, Pringles. You know, once one pops one just can't stop.

Howard: It's pretty late. You think I've got time to run some more simulations on the cooling system?
Leonard: Sure, I'm still figuring out the thermo-acoustic expander.
Sheldon: Oh, while you do that I am going to pump cerebral spinal fluid through my brain cells to remove the metabolic by-products of the day's thoughts.
Howard: What?
Sheldon: It's called sleep and it's my bedtime. Nighty-night, y'all.

Penny: Now Sheldon's popular? What is happening?!