Leonard: Ladies do love a guy dressed like a kitchen garbage bag.

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?

Raj: Amy, good luck getting these guys excited about a dinner with a theme. I gave up when no one cared about my Tom Hanks-Giving.

Sheldon: Let's see. What do I know about Amy? She loves medieval literature. Chaucer's her favorite. And her eyes sparkle when she watches old French movies. And I enjoy how harp music causes her fingers to dance as if she's playing along.
Bernadette: Wow, you really do love her.
Sheldon: I do. Now, let's find the kind of gift that makes her feel small and worthless.

Santa: All right, let me see if I've got this straight. A picture of you on my lap is a way to punish your girlfriend for making you celebrate Christmas?
Sheldon: Correct.
Santa: Santa thinks dating you might be punishment enough.
Sheldon: There's an argument for that, but I want to make sure.