Leonard: Sometimes your movements are so lifelike I forget you are not a real boy.

Raj: Oh, you're so arrogant. If you were a super hero your name would be Captain Arrogant. And do you know what your super power would be? Arrogance.

Sheldon: Oh, Penny. Penny.
Penny: What's up?
Sheldon: Nothing. I just wanted to make Raj stop talking.

Raj: Sorry, dude. The thermostat's on my side of the room, so it stays Mumbai hot in here until you turn off that stupid Indian music.
Sheldon: I'll turn off the music when you get rid of that salmonella-ridden parakeet.
Raj: Oh, too bad. Sheldon's pathologically afraid of birds. Hey, look, Sheldon. Birdie, birdie, birdie.
Sheldon: That's it. Prepare for marshmallow death.
Raj: Eat flaming Nerf.

Bernadette: What's George Takei doing here?
Katie Sackhoff: Howard, do you have latent homosexual tendencies?
Howard: Of course not.
George Takei: So you say, yet here I am.

Mrs. Wolowitz Howard, I found my girdle. It was in the dryer.
Howard: That's great, ma.
Mrs. Wolowitz I think it shrunk. I'm spilling out like the Pillsbury Doughboy here.

Sheldon: This isn't a desk. This is a Brobdingnagian monstrosity.
Raj: Is that the American idiom for giant, big-ass desk?
Sheldon: It's actually British.
Raj: Can you say it again for me?
Sheldon: Brobdingnagian.
Raj: One more time?
Sheldon: Brobdingnagian.
Raj: Now three times fast?
Sheldon: Brobdingnagian, Brobdingna-

Howard: I did a stupid thing.
Leonard: Yeah, I guessed that.
Howard: It was the kind of thing that makes it kind of hard to face her now.
Leonard: That covers anything from farting in bed to killing a homeless guy. Oh my God, you ran over a hobo.

Howard: For all we know Glacinda the Troll wasn't even a real woman. She could have been a fifty year old truck driver from New Jersey.

Sheldon: You're wrong again. If arrogance were my super power, my name would be Dr. Arroganto.

Mrs. Wolowitz: I think it shrunk. I'm spilling out like the Pillsbury Doughboy here.
Howard: And with that mental picture, I think we're done for the evening.

Howard: I love watching Raj and Sheldon try to work together.
Leonard: Yeah, it's like if Alien and Predator decided to go partners in a Jamba Juice.

Bernadette: Howard, a girl doesn't go out with a man like you, with your looks, your fancy patter, and your tight hoochie pants if she's not expecting him to eventually make the move.

Raj: I'm telling you, if xenon emits ultraviolet light, then those dark matter discoveries must be wrong.
Sheldon: Yes, well, if we lived in a world where slow-moving xenon produced light, then you'd be correct. Also, pigs would fly, my derrire would produce cotton candy, and The Phantom Menace would be a timeless classic.

Leonard: What are you doing in there?
Sheldon: I'm making hydrogen sulphide and ammonia gas. Just a little experiment in pest control.
Raj: It's not gonna work, dude. I grew up in India, an entire subcontinent where cows walk in the street, and nobody has ever had a solid bowel movement.
Sheldon: Well, we'll just see how long you can hold out.
Raj: Well, we'll just see how your noxious gas fares against my cinnamon-apple-scented aroma therapy candles.
Leonard: Didn't you say you're making hydrogen sulphide gas?
Sheldon: Yes.
Leonard: Isn't that flammable?
Sheldon: Highly. Oh, dear. [explosion]