Sheldon: I don't understand why you're not enjoying this. Together, in this car, with my enhanced capabilities, we're like 'Knight Rider.'
Leonard: Except, in Knight Rider, the car isn't a yammering sphincter.
Sheldon: You mock the sphincter, but, the sphincter is a class of muscle without which human beings couldn't survive. There are over 50 different sphincters in the human body. How many can you name?
Leonard: I was wrong. This is exactly like Knight Rider.

Sheldon: I'm no stanger to mimetic epidemiology. At Johnson Elementary school, the phrase Shelly Cooper's a smelly pooper spread like wildfire.
Amy: I should think so, that's gold.

Sheldon: (Knocking at Penny's door) Penny! Penny! Penny! Penny! Penny! Penny! Penny! Penny! Penny! Penny! Penny! Penny!
Penny: What the hell is wrong with you?
Sheldon: I'm the Flash, I just knocked 30 thousand times.

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

Sheldon: Oh, here's a fun fact. Ketchup started out as a general term for sauce, typically made of mushrooms or fish brine with herbs and spices. Some popular early main ingredients included blueberry, anchovy, oyster, kidney bean, and grape.

Penny: Hey, Sheldon, did you change your Wi-Fi password again?
Sheldon: Yes, it's "Penny get your own Wi-Fi"; no spaces.

Sheldon: Score 1 for liquor and poor judgement.

Sheldon: I gargled with tequila. I may have swallowed a tiny bit.
Leonard: You all right?
Sheldon: Fine, thank you for asking. I love you so much.

Penny: Oh, big deal. Not knowing is part of the fun.
Sheldon: "Not knowing is part of the fun." Was that the motto of your community college?

Howard: You gotta like this: the girlfriend, the ex-girlfriend, bonding over your rooty-tooty stinky booty? (All but Leonard laugh)
Leonard: Kill me.
Sheldon: It wouldn't help. The human body is capable of being flatulent for hours after death.

Amy: I was proposing massaging your muscles with your own hands.
Sheldon: Still sounds like a lot of unnecessary touching.

Sheldon: What are you doing here?
Howard: I've been up all night. I had a fight with Bernadette.
Sheldon: Why?
Howard: She bought me a nice watch.
Sheldon: Leonard, do you understand any of this?
Leonard: Yes.
Sheldon: Talk to him.

Sheldon: My hands are magic.

Sheldon: Oh Amy, I've never been touched like this before.

Sheldon: What are you doing here?
Leonard: I live here.
Sheldon: I have paperwork that says differently.