Leonard: It's two a.m. What are you doing up?
Sheldon: Nobel Prize acceptance ceremony streaming live from Stockholm.
Leonard: Sure. You want to see what all the scientists are wearing this year.

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.

Leonard: Do you think we can outrun him?
Sheldon: I don't need to outrun him, I just need to outrun you.

Penny: Did Sheldon change the Wi-Fi password again?
Leonard: Yeah, it's "Penny already eats our food she can pay for Wi-Fi". No spaces.

Sheldon: I'm not going to say I told you so, but we could have killed him.