Sheldon: I don't think I can go much longer.
Leonard: It's been three and a half minutes, wake up!

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

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?!