Lenny: I though you hate dogs.
Sheldon: A dog-opus can play fetch with eight balls. No one can hate that.

Penny: Honey, have you ever run before?
Sheldon: Certainly. I've run from bullies, dogs, angry chickens and one particularly persistent PE teacher determined to bend me over and give me a scoliosis test.

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: You're 15th favorite technological visionary.
Steve Wozniak: Only fifteenth?
Sheldon: It's still six spots above Steve Jobs. I care neither for turtlenecks nor showmanship.

Penny: Can I ask you a question?
Sheldon: Given your community college education, I encourage you to ask as many as possible.

Penny: OK. Well, then, there's a couple of things you should probably know.
Sheldon: I have a master's degree and two doctorates. The things I should know, I do know.

Sheldon: Amy pointed out that, between the two of us, our genetic material has the potential of producing the first in a line of intellectually superior, benign overlords to guide humanity to a brighter tomorrow.
Wolowitz: I'm guessing that future historians will condemn us for not taking this opportunity to kill Sheldon.

Apparently, a semi-incestuous Teens for Jesus hoedown didn't count.

You have broad hips and a certain corn-fed vigor. Is your womb available for rental?

At best, it's a modest leap forward from the technology that gave us Country Bear Jamboree.

That's not afternoon. That's prevening.

Sheldon: Hello, Amy Farrah Fowler. I'm sorry to inform you that you've been taken in by unsupportable mathematics designed to prey upon the gullible and the lonely. Additionally, I am being blackmailed with a hidden dirty sock.
Amy: If that was slang, I'm unfamiliar with it. If it was literal, I share your aversion to soiled hosiery.

TBBT Quotes

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

Sheldon: Why do you have the Chinese character for "soup" tattooed on your right buttock?
Penny: It's not "soup," it's "courage."
Sheldon: No it isn't. But I suppose it does take courage to demonstrate that kind of commitment to soup.
Penny: How'd you see it? You said you wouldn't look.
Sheldon: Sorry. As I told you, the hero always peeks.