Leonard: Hang on. Are you feeling insecure? Because that's my thing, and if you take it away, I don't know what I'm bringing to this relationship.

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.

Howard: Wow. I wonder what that guy could've done to make Sheldon not talk to him for 20 years.
Leonard: I wonder if it'd work a second time.

Penny: All right, this is making me crazy. Somebody's got to go over there.
Leonard: You got feet and legs, you do it.

Penny: So we're about to film this scene in the movie where the killer ape DNA is slowly taking over my body.
Leonard: Okay.
Penny: But I realize they're gluing fur everywhere except my cleavage. So I ask the director and he says it's important to the story that my boobs be the last things to turn ape.
Leonard: It's sweet that he thinks there's a story.

Amy: Hey, did you guys know that Sheldon had a best friend growing up named Tam?
Leonard: Was that the imaginary talking koala?
Amy: No. He's a real person who apparently betrayed him.
Leonard: Yeah, so did the koala.

Leonard: Look, this is your wedding, just pick whoever you want. You don't need to worry about anyone else but yourself. You've kind of been training for this your whole life.

Leonard: On the count of three, both of you bounce the balls as hard as you can. The highest bounce wins the office.
Barry Kripke: Oh, you are going down, Cooper.
Sheldon: I don't think so, Kripke. I've bounced many a rubber ball in my day.
Leonard: All right, that's enough trash talk. One, two, three.

Penny: Okay, what just happened?
Leonard: I don't know. Between you playing chess like Bobby Fischer and Sheldon being okay with you in his spot, I'm guessing someone went back in time, stepped on a bug, and changed the course of human events.

Howard: You look like you come with a kickstand.
Raj: You can't make me feel bad.
Howard: Hmm, maybe not. Leonard?
Leonard: So, when the aliens brought you back, they just left the probe in?

Guy: Is this guy for real?
Leonard: Boy, I wish I could say no.

Leonard: Ladies do love a guy dressed like a kitchen garbage bag.

Sheldon: Leonard, quick. I need you to get me to Arcadia within the hour. The train store's having a sale.
Leonard: Why can't Amy drive you?
Sheldon: Because of the tradition that I cannot see Amy on the day of the train store sale.
Leonard: Please, please see a doctor.

Priya: It's a little weird your ex-girlfriend hanging out here all the time.
Leonard: I know. I usually never see my ex-girlfriends, unless their hard drives crash.

Sheldon: I don't come into your house and touch your board.
Leslie: There are no incorrect equations on my board.
Sheldon: Oh, that is so... so...
Leslie: I'm sorry, I've got to run. If you come up with an adjective, text me.