Leonard: You, uh, moving in to the apartment on the fifth floor?
Cole: No, I was just visiting a friend.
Leonard: Oh, cool. The cute blond on four?
Cole: Yeah, you know her?
Leonard: I see her around. I like to keep my distance because her boyfriend is a pretty scary dude.
Cole: Really?
Leonard: Yeah. He's ganged up.
Cole: She told me he's a scientist.
Leonard: That's the name of his gang. The Scientists. They're crazy.
Cole: Well, thanks for the tip.
Leonard: No problem, brother. Stay frosty.

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.

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

Sheldon: You may not realize it, but I have difficulty navigating certain aspects of daily life. You know, understanding sarcasm, feigning interest in others, not talking about trains as much as I want. It's exhausting!

Sheldon: (Playing hackey sack) One, two, three, four, five, six, seven, eight. Drat. I'm never going to get to forty-three again. One, two, three, four. Rats.

Penny: Hey! Shouldn't you be out with your gang spray painting equations on the sides of buildings?