Howard: He compared Sheldon to a disposable feminine cleansing product one might use on a Summer's Eve.
Penny: Yeah and the bag it came in.

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: Teams are traditionally named after fierce creatures thus intimidating one's opponent.
Raj: Then we could be the Bengal tigers.
Sheldon: Poor choice. You know, gram for gram no animal exceeds the relative fighting strength of the army ant.
Raj: Maybe so, but you can't incinerate a Bengal tiger with a magnifying glass.

Wolowitz: That's more like we're a tall thin woman who wants to make a coat out of your Dalmatians.

Raj: I say we wait until he looks at us then laugh, like "Yes, you're a smart and strong competitor but we're also smart and strong and we have a reasonable chance of defeating you".