Penny: Ok, here you go Leonard. One tequila sunrise!
Leonard: Thank you! You know, this drink is a wonderful example of how liquids with different specific gravities interact in a cylindrical container!

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?

Leonard: I don't believe it. What's gotten into him?
Penny: Oh, maybe a couple of virgin Cuba Libres that turned out to be kinda slutty.
Leonard: You didn't.
Penny: Hey, you do your experiments, I do mine.

Raj: How can I be a gynaecologist? I can barely look a woman in the eye!

Sheldon: How often does one see a beloved fictional character come to life?
Wolowitz: Every year at ComiCon. Every day at Disneyland. You can hire Snow White to come to your house. Of course they prefer if you have a kid.