Howard: Behold the Mobile Omni-Directional Neutralization and Termination Eradicator! Or...
Leonard, Sheldon, Howard, Raj: Monte.

(Leonard is pointing out the monotonous movie habits of their former relationship.)
Leonard: No. You always picked, and it was always the same. An hour and a half of beach houses in the rain until the woman turns around and realizes love was here all along.
Penny: But, come on, that is a great movie, and it starts in ten minutes.

Leonard: All I'm saying is, if they took all the money they spent trying to make a decent Hulk movie, they could probably make an actual Hulk.

Leonard: If I roll down the windows, everything is peachy. If you roll down the windows, you're still not a doctor.

Leonard: Do you realize I don't live with the woman I love because of you? No other reason. Just you.
Sheldon: Is that true?
Leonard: Yes, it's true. The last time I brought it up, you had an emotional breakdown, got on a train, and ran away.

Leonard: Wait, wait, is 'brought' right?
Sheldon: Marty never had have had brought?
Leonard: I don't know, you did it to me.

Sheldon: Apparently I have a reputation for being "obnoxious".
Leonard: Whaaaaaat?

Leonard: (Helping Althea with the crossword puzzle) One across is Aegean, eight down is Nabokov, 26 across is MCM, fourteen down is-- move your finger, phylum, which makes 14 across Port-au-Prince. See, Papa Doc's capital idea, that's Port-au-Prince. Haiti.

Leonard: My parents focused on celebrating achievements and being expelled from a birth canal was not considered one of them.

Penny: What is this?
Leonard: Oh, careful. That's my original series Battlestar Galactica flight suit.
Penny: Oh, why didn't you wear it on Halloween?
Leonard: Because it's not a costume, it's a flight suit.

Leonard: Nice to know everything's OK with your plumbing. Err, the building's plumbing.

Penny: (crying) How could he do that?
Leonard: Oh, you did throw an 80-gig iPod-- Yeah, no, how could he do that?

Leonard: Open the landing bay doors, shuttle craft approaching.

Leonard: What do you mean it happened again?!

Penny: Well should we wake him up?
Leonard: Well, he did say if he fell asleep, we were allowed to slap him awake.
Penny: Oh, boy.
Leonard: Wait a minute. Why do you get to do it?
Penny: 'Cause I called it.
Leonard: Well, you can't just call it. You have to earn it.
Penny: Oh, and you've earned it?
Leonard: No one has earned it more than me. [Amy clears her throat] You have your whole life to smack him around. This is my time.