Wolowitz [about his phone call]: Looks like I'm going to have sex tonight
Penny: His right hand is calling him?

I'm from Nebraska. When we shoot things, it's because we want to eat em' or make them leave our boyfriends alone

Penny

Leonard: You know what baffles me Sheldon?
Sheldon: Based on your academic record, I could guess any number of things

Penny: What are we gonna do?
Leonard: We? No, no, no. You had your chance to be "we" for like a year and a half now. Right now, you are you and you are screwed.

Leonard [about his mother]: She's only been here a day and a half, and I'm seriously considering alcoholism as a new career path.
Penny: Hey, I talked to her for five minutes yesterday, and I've been half bombed ever since.

At that age, he was well enmeshed in what Freud would call the Phallic Stage of psycho-sexual development; an outmoded theory, of course, but the boy did spend most of his waking hours with a tight grasp on his penis

Mrs. Hofstadter [describing Leonard at age 6]

Penny: What was Leonard like when he was little?
Mrs. Hofstadter: Oh, I think you mean "young." He's always been little.

Penny [about his mom]: You can't let her get into your head
Leonard: It's too late for me, my head is her summer house

Mrs. Hofstadter [about Penny]: If you want to have sex with that woman, find out what kind of cologne her father wore
Leonard: Hello mother

Leonard: Okay, is everyone clear on the plan?
Wolowitz: Yes. Koothrappali is going to wet himself, I'm going to throw up, Sheldon is going to run away, and you're going to die. Shall we synchronize our watches?

Leonard: What was the plan?
Penny: Um, waitress for six months and then become a movie star.
Leonard: Was there a Plan B?
Penny: TV star.

You know, I've given the matter some thought, and I think I'd be willing to be a house pet to a race of super-intelligent aliens.

Sheldon

TBBT Quotes

Oh, Bernadette, please play my clarinet.

Raj's poem

Sheldon: I'll have a diet Coke.
Penny: Can you please order a cocktail? I need to practice mixing drinks.
Sheldon: Fine... I'll have a virgin Cuba Libre.
Penny: That's... rum and Coke without the rum.
Sheldon: Yes, and would you make it diet?