Leonard: Face it, Raj, we crashed and burned tonight.
Mrs. Latham: Oh, you didn't do that badly.
Leonard: Mrs. Latham, the first machine I turn on in the morning is the helium-neon laser, 'cause it needs to warm up.
Mrs. Latham:: I no longer care, dear.

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: 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.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Penny: Good morning, slut!
Leonard: What?
Penny: Oh, please! I recognise the walk of shame when I see it. All you're missing is a little smeared mascara and a purse with panties wadded up in it!

Sheldon: Given how much time you spend engaging in pointless self-abuse, you might consider, just this once, using your genitalia to actually accomplish something.

Sheldon: An entire dinner to talk about your research? Where you going? The drive thru at Jack In The Box?