Colonel Williams: Just wanted to see how the guidance system's coming along.
Howard: Great. We found a cooling solution that allowed us to get the size of the prototype down to the target specs.
Leonard: As a cooling solution, it's pretty cool.
Colonel Williams: Don't do that.

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.

Howard: How'd you even get that up the stairs?
Sheldon: I said to myself, "I think I can, I think I can." And then I couldn't, so I paid two men who promised not to come rob us later.

Colonel Williams: What's this?
Leonard: Oh, nothing. Just some math we don't need.
Colonel Williams: This is a different approach. Are you trying to get the guidance system even smaller?
Leonard: It's just a theory. Uh, it's not even worked out.
Colonel Williams: Oh. I want this.
Howard: But we've already met the agreed upon specs. Going smaller would require weeks' worth of new computations.
Colonel Williams: So get the kid with the two shirts to do it.

Leonard: You know, I do have a way to get him out of our hair. I've been holding onto this for a few years, but maybe now's the time.
Howard: We can just lock the door; you don't have to kill him.
Leonard: You can't kill him; he'll just respawn at the last save point.