Sheldon: Oh Lord, this can't be more humiliating.
Leonard: No, no, no, give him a minute.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Penny: So what do you say Sheldon, are we your X-men?
Sheldon: No, the X-men were named for the X in Charles Xavier. Since I am Sheldon Cooper, you will be my C-men.

Sheldon: I see. I assume since the rest of you have set the bar so low, you're saving the most impressive contribution for last. Go on Howard, dazzle me.
Howard: Well, my power is the ability to pretend like I give a damn about your piddly-ass problem. And that's 24/7 buddy.

Sheldon: A neutron walks into a bar and asks how much for a drink. The bartender replies "for you, no charge".