Leonard: You know what? I am tired of living in fear of this guy. I'm gonna go see him and finally say all the things I should have said in high school. You know, "Pick on someone your own size. You did not have sex with my mother. And yes, I do know why I'm hitting myself."

Leonard: I'm going to the movies with Penny. I don't want her to think I think it's a date.
Sheldon: Do you think it's a date?
Leonard: No, but she might think I think it's a date even though I don't.
Sheldon: Or you might think she thinks you think it's a date even though she doesn't.
Leonard: Are we over thinking this?
Sheldon: Not at all.

Leonard: Star Wars on Blu-ray.
Penny: Haven't you seen that movie like a thousand times?
Leonard: Not on Blu-ray. Only twice on Blu-ray.
Penny: Oh, Leonard.
Leonard: I know, it's high resolution sadness.

(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: You didn't see me telling Kevin that you thought Cold Wars were only fought in Winter

Penny: Well, I'm going to take myself out to a movie tonight. You want to go?
Leonard: Really? Do we do that?
Penny: What do you mean?
Leonard: You know, we haven't spent time alone together since we broke up.
Penny: Oh, it's not a date, Leonard. It's just a man and a woman hanging out, and not having sex at the end of the night.
Leonard: Sounds like most of my dates.

Sheldon: [inside the apartment] Oh, dear Lord, get away from me, you monster!
Penny: [in the hallway] What is that about?
Leonard: Well, he's smart and crazy enough, he may have actually created a monster.

Leonard: See? Now, that's the great thing. We're out as friends. This is not a date. Sex is off the table. So, let's go learn why hydroelectric power might not be the environmental bargain you think it is. Sorry. Spoiler alert.

Leonard: I'm going to get some fries. You want anything?
Penny: Uh, no, thanks.
Leonard: Are you sure? Because you always say no, and then you eat half my fries.
Penny: I just eat the little crispy ones you don't like.
Leonard: No, I love them. I save them for the end, but they're gone because you ate them. And why did I let you eat them?
Penny: To get sex.
Leonard: Exactly.
Penny: All right, I'd like an order of fries.
Leonard: Great. That'll be five dollars. I am having the best time. I'm so glad you suggested we do this.

Leonard: When you were telling Kevin about your acting career, did you mention your long-running role as Waitress in a local production of The Cheesecake Factory?

Leonard: Come on, she's your friend. Step up! [Knock * 3] Amy. [Knock * 3] Amy. [Knock * 3] Amy. (Turns to leave) Bye!
Sheldon: Where are you going?
Leonard: I'm single, I don't need this crap.

Leonard: Amy, how long would it take for that mad cow disease to kill me?
Amy: I don't know, four or five years.
Leonard: No, it's not gonna do it.

Leonard: Leonard's coming down the home stretch. Come on, horsey, you can do this Damn. Come on, thigh muscles, you can do this. Yes, first place! I would have been a great jockey if I weren't too tall. And scared of horses.

Raj: I'm thinking about adopting some quirky affectation, like a pipe or a monocle or a handlebar moustache.
Leonard: For all those girls out there looking for the Indian Monopoly man?

Penny: Where's Sheldon?
Leonard: Oh, he was up late last night, so I gave him an early dinner and put him to bed.
Bernadette: That's so sweet.
Leonard: Yeah, but now he's gonna be up at dawn and want to play.