Leonard: A joke. Okay. How about this, um, okay, uh there's this farmer, and he has these chickens, but they won't lay any eggs. So, he calls a physicist to help. The physicist then does some calculations, and he says, um, I have a solution, but it only works with spherical chickens in a vacuum.

Wolowitz: Raj, did you ever tell your sister about the time Sheldon got punched by Bill Gates?
Priya: Oh, God, you're kidding.
Raj: No, Gates gave a speech at the university. Sheldon went up to him afterwards and said, "Maybe if you weren't so distracted by sick children in Africa you could have put a little more thought into Windows Vista."
Leonard: Bam, right in the nose. Made me proud to own a PC.

Leonard: Yeah, that would be a little more like getting into dracula's coffin.

Leonard: (To Raj) I'd like to kick your little brown ass.

Leonard: (To Raj) No, we don't want to watch Bridget Jones' Diary.

Leonard: What ya doin' there? Working on a new plan to catch the Road Runner?

Leonard: I bet I could throw a rock in this room and come up with three better friends!

Leonard: You convinced me. Maybe tonight we should sneak in and shampoo her carpet?
Sheldon: You don't think that crosses a line?
Leonard: Yes! For God's sake, Sheldon, do I have to hold up a sarcasm sign every time I open my mouth?
Sheldon: You have a sarcasm sign?

Stephanie: So, how was your day?
Leonard: You know, I'm a physicist, I thought about stuff.
Stephanie: That's it?
Leonard: I wrote some of it down.

Leonard: Merry Newtonmas everyone.

Penny: What about Howard and Raj? How did he become friends with them?
Leonard: I dunno. How do carbon atoms form a benzene ring? Proximity and valence electrons.
Penny: Sure, when you put it like that.

Leonard: Twelve years after high school and I'm still at the nerd table.

Raj: Guys, I just did a quick calculation. Judging by the size of the theater and this line we may not get in.
(Sheldon wakes up and jumps out of his chair.)
Sheldon: What did he say?
Leonard: Nice going, Raj. I just got him down for his nap.

Penny: I can't believe you've never read "Eat, Pray, Love".
Leonard: When she comes out with "Eat, Pray, Runaway from a giant boulder", I'll read it.

Leonard: Would someone please turn off the Sheldon commentary track?