Amy: I just read about an experiment designed to see if you can make two people fall in love in a matter of hours.
Leonard: That doesn't sound right. My research has shown that it takes three to five years of shameless begging.

Let's have a toast. To Mrs. Wolowitz. A loving mother ... to all of us. We'll miss you.

Sheldon: I didn't care for her yelling, but now that I'm not going to hear it again, I'm sad.
Leonard: If you want, I can yell at you later.
Sheldon: It won't be as good.

Nathan Fillion: How about a guy who looks like Nathan Fillion, but a little more annoyed than Nathan Fillion usually is?
Leonard: What do you think?
Raj: Aww. That's good enough for Facebook.

Raj: The guy who plays Jon Snow was a jerk and we still watch Game of Thrones.
Leonard: He was a jerk because you rear-ended him.
Raj: I was distracted. It's weird seeing a member of the Night's Watch with kayak strapped to his car.

Leonard: Stephen Hawking liked our paper. Said the premise is intriguing.
Sheldon: Good to see you again, Mr. Stephen-Hawking- Liked-Our-Paper.
Leonard: And you as well, Mr. Our-Premise-Is-Intriguing.
Howard: How do you do, Mr. I'll- Admit-That's-Pretty-Cool?
Raj: Yeah, you keep setting me up for failure.

Sheldon: Professor Hawking?
Professor Hawking: Oh, brother, you should see the look on your faces.
Leonard: You really didn't like our paper?
Professor Hawking: I like your paper very much. The premise is intriguing.
Sheldon: Then why are you attacking us?
Professor Hawking: If you were sitting in a chair for 40 years, you'd get bored, too. Anyway, got to go. I promised to help the neighbor kid with his math homework. Ciao.

Leonard: Uh, another one says, "The concept shows some real out-of-the-box thinking".
Sheldon: Do you hear that, Mr. Out-Of-The?
Leonard: I do, indeed, Mr. Box-Thinking.

Leonard: You're sure it's good?
Sheldon: My name is right on there with yours. That is a surefire
mark of quality. That might as well say "Directed by Joss Whedon".
Leonard: Okay, partner, let's do it.

Leonard: You wrote a paper on my idea?
Sheldon: I wrote a paper on our idea.
Leonard: When did my idea become our idea?
Sheldon: When I mixed it with Sheldony goodness and cooked it in the Easy-Bake Oven of my mind.
Leonard: This is good. Our idea is really good.
Sheldon: Well, the light bulb in this oven is ridiculously bright.

Leonard: You're giving me a sticker?
Sheldon: Not just a sticker. That is a sticker of a kitty saying, "Me-wow!"
Leonard: I'm not a preschooler.
Sheldon: Fine, I'll take it back
Leonard: I earned this! Back off!

Leonard: This... is exciting. This is really exciting. I have to go find Sheldon.
Penny: Okay, well, if you find him, use the kitchen island- that coffee table will not support both of you.

TBBT Quotes

Sheldon: Are you still mad about the sperm bank?
Leonard: No!
Sheldon: Do you want to hear an interesting thing about stairs?
Leonard: Not really.
Sheldon: If the height of a single step is off by as little as two millimeters most people will trip.
Leonard: I don't care—two millimeters?! That doesn't seem right.
Sheldon: No, it's true! I did a series of experiments when I was twelve; my father broke his clavicle.

Penny, there's only one cookie with something in the middle that solves life's problems, and that's an Oreo. Or a Nutter Butter, if you're in a pinch.

Sheldon