Sheldon: Given how much time you spend engaging in pointless self-abuse, you might consider, just this once, using your genitalia to actually accomplish something.

Sheldon: Hi, Mom, how are you?But, Mom, she keeps sitting in my spot. And she touched my food. Okay, yes, I took her clothes, but she started it. (throwing a fit) No, that's not fair. Why should I have to apologize? I really don't think this is the kind of thing Jesus concerns himself with. No, you're right. I don't really know what Jesus thinks about. All right! Goodbye. (hangs up) (to Leonard) Did you tell on me?
Leonard: Are you kidding me? I already have 2 strikes

Sheldon: Leonard, I don't think I can do this.
Leonard: What are you, kidding? You're a semi-pro.
Sheldon: No, we are committing genetic fraud. There's no guarantee that our sperm's going to generate high-IQ offspring. Think about that. I have a sister with the same basic DNA mix who hostesses at Fuddruckers.

Sheldon: Of the handful of women Leonard's been involved with, she's the only one I have ever found tolerable.
Penny: Well, what about me?
Sheldon: The statement stands for itself.

Sheldon: There's a fine line between wrong and visionary. Unfortunately, you have to be a visionary to see it.

Sheldon: Frankly, Mom, I'm encouraged to see how advanced your group has become -- willing to sail into the ocean without fear of falling off the edge.

Leonard: We'll miss you Sheldon.
Sheldon: Yeah, well, who wants to spend the whole weekend, running around a bunch of pretend planets, battling made up monsters? That's for babies.
Howard: Yeah, but it's got lightsabers.
Sheldon: Please, Amy! It's got lightsabers!

Leonard: You know what, go to Hell and set their thermostat.
Sheldon: I don't have to go to Hell. At 73 degrees, I'm there already!

Sheldon: I know mother, but you're not fooling me. Every time you want to talk it means you want me listen.
Mrs. Cooper: Then stop talking.
Sheldon: Yes, Ma'am.

Sheldon: Don't worry. I will remain the same down to earth, humble Joe I've always been.
Leonard: Good to know.
Sheldon: Now give me that cookie, I discovered an element.

Sheldon: Amy, when I look in your eyes and you're looking back in mine, everything feels not quite normal. Because I feel stronger and weaker at the same time. I feel excited and, at the same time, terrified. The truth is, I don't know what I feel, except I know what kind of man I want to be.
Amy: Sheldon, that was beautiful.
Sheldon: I should hope so, that's from the first Spider-Man movie.
Amy: I'll take it.

Sheldon: You know, I'm given to understand that there's an entire city in Nevada devoted specifically to help people like Howard forget their problems. They replace them with new problems such as alcoholism, gambling addiction and sexually transmitted diseases.

*After getting a spare in the bowling match*
Sheldon: Thank you, Jesus! As my mother would say.

Sheldon: Who's Nowitzki?
Ramona: I'm Nowitzki.
Sheldon: Oh, so you want me to share credit with you?
Ramona: Uh huh.
Sheldon: Get out!

Sheldon: She's remarkable.
Leonard: She really is.
Sheldon: How is it that she can remember all those lines, yet as a waitress she can't remember no tomato on my hamburger?