Penny: You know, on our first date, Leonard used a coupon to buy me a pretzel.
Leonard: And we lived happily ever after.
Penny: The end.

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

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.