Raj: Dance number aside, I'm so not gay.

Penny: Mrs. Cooper? Hey, it's Penny. I think I broke your son. Hold on. Talk to your mother.
Sheldon: (Crying) Mommy, I love you. Don't let Spock take me to the future!

Raj: I know the feeling. It's like accidentally walking into a gay bar and then having no one hit on you. It happened to a friend of mine.

Raj: Cute is for bunnies. I want to be something with sex appeal. Like a labradoodle.

Sheldon: Well, I suppose everyone's entitled to their own opinion. I think I'll turn in. I didn't wanna teach those poopy heads anyway.
Howard: FYI, I think that's what Darth Vader said just before he started building the Death Star.

Penny: Okay, that's fine, but let's try and get you out of your comfort zone.
Sheldon: Why would we want to do that? It's called the comfort zone for a reason.

Sheldon: I was expecting applause but I suppose stunned silence is equally appropriate.

Penny: (Reading tweet) "Listening to Dr. Cooper has made me wanna start cutting myself again."

Sheldon: I agreed to speak to you this evening because I was told that you're the best and the brightest of this university's doctoral candidates. Hmm. Of course, that's like saying you are the most important electron in a hydrogen atom. 'Cause you see, there's only one electron in a hydrogen atom. Best and brightest my sweet patootee. All right, let's begin. Show of hands, who here is familiar with the concept of topological insulators? Don't kid yourselves.

Sheldon: I sense that you're trying to slow walk me to an epiphany. Would you mind very much jumping to it.

Sheldon: Action.
Penny: Okay, it's not a movie. It's improv. So no one calls action.
Sheldon: Hey, you taught me something. Who would have thought that.

Amy: Well, the first thing that comes to mind is isolating the part of your brain where the memory is stored and destroying it with a laser.
Sheldon: Hmm, no. One slip of the hand and suddenly I'm sitting in the Engineering Department, building doodads with Wolowitz.

Leonard: I'm still not adjusted to how the SyFy channel spells their name now. S-Y-F-Y, that's siffy.

Penny: Okay, Cat on a Hot Tin Roof is an American classic.
Sheldon: So is the McRib sandwich. I don't care for that either.

Penny: (On the phone) Mrs. Cooper, hey, it's Penny. Yeah, I think I broke your son. Hey, hold on. Talk to your mother.
Sheldon: Mommy, I love you. Don't let Spock take me to the future!