Penny: I'm a vegetarian. Well, except for fish, and the occasional steak. I love steak!
Sheldon: Well, that's interesting. Leonard can't process corn

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.

Leonard [referring to him and Penny]: Our babies would be smart and beautiful.
Sheldon: Not to mention imaginary

[at the high-IQ sperm bank discussing donating...]
Sheldon: What if she ends up with a toddler who doesn't know if he should use an integral or a differential to solve for the area under a curve?
Leonard: I'm sure she'll still love him.
Sheldon: I wouldn't

Penny: I'm a Sagittarius, which probably tells you way more than you need to know.
Sheldon: Yes, it tells us that you participate in the mass cultural delusion that the sun's apparent position relative to arbitrarily defined constellations at the time of your birth somehow affects your personality.
Penny: Participate in the what?

Leonard: We need to widen our circle.
Sheldon: I have a very wide circle. I have 212 friends on MySpace.
Leonard: Yes, and you've never met one of them.
Sheldon: That's the beauty of it

Leonard: At least I didn't have to invent 26 dimensions just to make the math come out.
Sheldon: I didn't invent them, they are there!
Leonard: In what universe?
Sheldon: In all of them, that's the point

Sheldon [to Kripke]: Also, I am given to understand that your mother is overweight.
Raj: Oh, snap.
Sheldon: Now of course, if that is the result of a glandular condition and not sloth and gluttony then I withdraw that comment.

TBBT Quotes

I won't say that all senior citizens who can't master technology should be publicly flogged, but if we made an example of one or two, it might give the others incentive to try harder.

Sheldon

Sheldon: Why do you have the Chinese character for "soup" tattooed on your right buttock?
Penny: It's not "soup," it's "courage."
Sheldon: No it isn't. But I suppose it does take courage to demonstrate that kind of commitment to soup.
Penny: How'd you see it? You said you wouldn't look.
Sheldon: Sorry. As I told you, the hero always peeks.