Leonard: It's going to be difficult to find something you are both equally good at.
Raj: Is there anything you are both equally bad at?
Sheldon and Kripke: Sports.

Sheldon: I'm trying to raise the temperature in here before my nipples tear through my shirt.

Sheldon: Boy, oh, boy. This vacation is off to a wonderful start. The smell of formaldehyde, the whir of the centrifuge, the distant chatter of lab animals being dispatched for dissection. Mm, I can already feel my cares just melting away.
Amy: I'm excited to work with my boyfriend. It's going to be romantic.
Sheldon: Way to kill the mood.

Sheldon: This is now the only lab with glassware washed by a man with two doctorates and a restraining order signed by Carl Sagan.
Amy: Soap spots. Wash them again.

Howard: Hope you don't mind, I told my girlfriend, Bernadette, she can join us for dinner.
Leonard: Sure, the more the merrier.
Sheldon: Wait, no. That's a false equivalency. More does not equal merry. If there was 2000 people in this apartment right now, would we be celebrating? No, we'd be suffocating.

Sheldon: Hear me out. The atomic bomb was the Manhattan project, Windows 95 was Project Chicago, for our app I humbly suggest Project Nodlehs.

Sheldon: Yes, this is doctor Sheldon Cooper. Is this the Zack Johnson that used to have coitus with my neighbour Penny? Sorry to bother you. (to different person) Hello I'm looking for a Zack Johnson that used to have coitus with my neighbour Penny. Coitus. It means intercourse and I have a feeling I'm speaking to the right Zack.

Sheldon: Biologists are mean.

Sheldon: You've got the brilliant Sheldon Cooper in your lab and are going to ask him to do the dishes? That's like asking the Incredible Hulk to open a pickle jar.

Sheldon: Hawaii is a former leper colony on top of an active Volcano where the disappointing ending to Lost was filmed. Mahalo for nothing, Hawaii.

Sheldon: This place could really use a suggestion box.

Penny: Hay Leonard, check this out. * Throws won-ton in the air and catches it in her mouth *
Sheldon: Leonard, she's doing it again.
Leonard: I think it upsets Sheldon when you play with the food.
Sheldon: No, it upsets Sheldon when she willy-nilly takes it from the containers with out guard of equitable distribution. * Turns to Raj * This is essentially why you have famine in India.
Penny: You want me to put it back? *Said with mouth full of food *
Sheldon: Leonard!
Leonard: It upsets Sheldon when you play with the Sheldon.

Sheldon: I would have been here sooner but the bus kept stopping for other people to get on it.

Sheldon: You're my girlfriend and you're not going to cater to my every need? Where'd the magic go?

Sheldon: Wine and a girl in the dark. He's going to be bored out of his mind.