Sheldon: That's a lot of belt buckles.
Howard: Funny thing is, I have only one belt. Anyway, I'll get you started. Oh, by the way, the little marks that look like water spots, I tend to stand too close to the urinal, so what you're seeing there is splash back.
Sheldon: You make sissy on your belt buckles? Mee-Maw's forks never had that.

Sheldon: Oh, Leonard, I have something for you. Per our roommate agreement, this is your 24-hour notice that I will be having a non-related female spending two nights in our apartment.
Leonard: When you say non-related female, you still mean human, right?
Sheldon: Of course. Pets are banned under the roommate agreement, with the exception of service animals, such as seeing eye dogs and, one day, cybernetically enhanced helper monkeys.

Leonard: Why is a world-renowned scientist staying in our apartment instead of a hotel?
Sheldon: Well, she doesn't care for hotels. And who can blame here? Windows that don't open, multi-user linens, keys shaped like credit cards, as if one walks around with unassigned slots in one's wallet.

Sheldon: A word of warning. My guest is a noted physicist and the leading expert on quantum cosmology, so please try to avoid wasting her time with female jibber jabber.
Penny: Female jibber jabber?
Sheldon: Shoe sales, hair styles, mud masks, gossip about your friends Brad and Angelina.
Penny: Oh, they're not my friends.
Sheldon: I'm not surprised, considering the way you talk about them behind their backs.

Sheldon: In here you'll find emergency provisions. An eight-day supply of food and water, a crossbow, season two of Star Trek: The Original Series on a high-density flash drive.
Elizabeth: What if there's a disaster that destroys all the USB ports?
Sheldon: Then there's really no reason to live, is there?

Amy: Have I ever told you you're like a sexy praying mantis?
Sheldon: Every time you drink alcohol.

Raj: Waiter? A bottle of champagne and three glasses. Oh boy, isn't this romantic?
Sheldon: Oh, I hope that's a rhetorical question, because I have no clue.

Howard: He's just decided he's never leaving his apartment again.
Sheldon: Oh, brilliant. I've been itching to pull that trigger.

Howard: He's upset because he can't get anywhere with women.
Sheldon: Would it help if I gave him some pointers?
I'm just funnin' ya.

Sheldon: What's wrong?
Penny: I just think it might look more natural if you talked to me instead of the camera. You know, like a real conversation. It's something we work on in my acting class.
Sheldon: Interesting. A few people in the comments section have said that my delivery is robotic. Perhaps that's not the compliment it sounds like.

Penny: Let's try it again, and maybe this time, you could work on your body language a bit. You know, when you're all hunched like that, you're shutting the audience out, but when you're relaxed and open, you're inviting them in.
Sheldon: Right. And which one do I want?

Leonard: Why don't you just eat in your desk chair?
Sheldon: Why don't I just eat in my desk chair?
Penny: Here we go.
Sheldon: That is my desk chair, that's where I work. I don't eat in my desk chair and I don't work in my spot. I work in my desk chair and eat in my spot.

Raj: Did you guys see the new budget memo that went out this morning?
Leonard: Yeah, more cutbacks.
Sheldon: Unacceptable. It baffles me why they don't simply let some of you go so that there's money available for my research.

Leonard: You know what baffles me, Sheldon?
Sheldon: Based on your academic record, any number of things, I would imagine.

Sheldon: That is my spot. In an ever-changing world, it is a single point of consistency. If my life were expressed as a function on a four-dimensional Cartesian coordinate system, that spot at the moment I first sat on it would be zero-zero-zero-zero.