Leonard: What were you doing at Penny's?
Sheldon: Well, we had dinner, played some games, and then I spent the night. Oh, and you'll be happy to know that I now have a much better understanding of "friends with benefits"

Wolowitz: First we let the lawyers and the jock thin the heard, then we go after the weak, the old and the lame
Leonard: That's your system?
Wolowitz: Yeah and if you spot a girl with a seeing eye dog, she's mine

Wolowitz: Okay! Let me just go inside and slip off my underwear.
Leonard: Why?
Wolowitz: Well if I get lucky, I certainly don't want to be caught in my Aquaman briefs.

Leonard: I just don't get what she sees in Stuart, we're practically the same guy
Sheldon: ...Stuart is taller, artistic, self employed, and most importantly, gets 45% off comic books

Penny [at comic book store]: Everyone's staring at me!
Leonard: Don't worry, they're more scared of you than you are of them
Penny: Unlikely

Leonard: But we all agreed the third Thursday of every month will be "Anything Can Happen Thursday"
Sheldon: Apparently the news didn't reach my digestive system, which when startled has it's own version of "Anything Can Happen Thursday"

Sheldon [looking for musical instrument in new neighbor's boxes]: Do those sound like castanets to you?
Leonard: The box says "kitchen."
Sheldon: So? Do cocaine smugglers write "cocaine" on the box?

Penny: It looks like the MySpace page of a 13 year old girl
Leonard: No it doesn't
Wolowitz: Oh please, Dateline could use it to attract predators

Howard: you know what would bea great idea? We get some girls over here and we play laser obstacle strip chess
Leonard: Believe me howard, any girl who would want to play that, you don't want to see naked
Howard: You underestimate me

Leonard: Well, it seems once again you're caught between a rock and a crazy place.
Sheldon: Oh, I hate when that happens.

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.

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