Leonard: Hey, guys, what are you? Oh, that's here, cool.
Penny: Amy wants me to have it.
Amy: Well, it would be selfish of me to keep it.
Penny: But it's a picture of you.
Amy: And you.
Penny: But you commissioned it.
Amy: To give to you.
Penny: But you like it so much.
Amy: So do you.
Penny: I seem to be losing.
Leonard: Yes, you do.

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: It's not my fault I'm bad at sharing; I skipped kindergarten.

Sheldon: If it's like your 3-D chess game, then you're out of your length, width and depth. Amy, get the Neosporin, somebody just got burned.

Raj: Hey, this pregnancy had an emotionally-needy third wheel way before you came along.