Penny: Look, sweetie, relationships aren't about money, okay? It's about respect and having things in common and- Yes, Sheldon?
Sheldon: You and Leonard don't have anything in common. Maybe you should break up.
Leonard: (To Penny) You called on him.

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: Who's ready to laugh? [Leonard groans] Okay. So Feynman, Einstein and Schrodinger walk into a bar. Feynman says, "It appears we're inside a joke." Einstein replies, "But only to an observer who saw us walk in simultaneously." To which Schrodinger says, "If someone's looking in the window, I'm leaving."
Leonard: [chuckles] That's actually funny.
Raj: You should send that to Jimmy Fallon.

Raj: Sheldon, what did Amy have that attracted you?
Sheldon: Oh, so many things. Her mind, her kindness, and especially her body.
Raj: Really?
Amy: Relax. We're the same blood type. He knew he could harvest an organ.

Penny: So, Bert, you were telling us how you updated your profile?
Bert: Right. I wasn't getting any responses, and then I added, "Recent $625,000 MacArthur grant winner", and five minutes later, I met my soul mate.
*Amy goes to the hallway*
Amy: I was wrong. You can come back in.