Leonard: It was pretty cool.
Penny: Aw, so cute when you use the word "cool" wrong. Like when kids say "pasghetti."

If they didn't want to be yelled at by crazy nerds, they shouldn't have started a sci-fi channel.

Sheldon: Why would the Chinese make our DVR record Paul Blart: Mall Cop?
Leonard: I don't know. It's a fat guy on a Segway. That's funny everywhere.

Leonard: Oh, you do what you want, but I don't want to lose my friends over tenure. Friends are forever.
Howard [coughing]: So, is tenure.

Way to hit'em with both barrels.

Seriously, is that tape? Like, how are they staying up like that?

Amy

Leonard: You realize you might kill some of them.
Penny: Oh, then you all can get tenure.

Leonard: Mmm, you know, we could throw a dinner party too. Maybe even ask everyone to get dressed up.
Penny: Sure. Just when you say "dressed up" you mean nice clothes, right? Not, like, capes and tights and crap
Leonard: Although...
Penny: No.

Howard: Last time I was here, I was a scrawny little nerd.
Leonard: And, now, you're also an astronaut.

Sheldon: I believe in a gender blind society like in Star Trek. Where women and men of all races and creeds worked side-by-side as equals.
Leonard: You mean where they were advanced enough to develop an interstellar warp drive, but a black lady still answered the space phone?

Leonard: Helping women?
Sheldon: Helping anyone. People should take care of themselves.
Leonard: Oh, like yesterday when you made me drive you to the dry cleaners, the pharmacy and the post office?

Penny: Leonard Hofstadler...
Leonard: Yes?
Penny: Will you be my valentine?
Leonard: Sorry. Maybe, next year. ... I'm just kidding. Romance ninja. Let's have sex! Wah!

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.

It's very simple. Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and, as it always has, rock crushes scissors

Sheldon