Leonard: You make a lot of sense. I like this table and I'm getting it.
Penny: Really, this one?
Leonard: That one.
*Penny nods*
Leonard: Damn right I like that one.

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.

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: 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.

Bernadette: I think what we're all trying to say is that you don't seem to be remembering how traumatic the experience was for you.
Raj: Like how women often forget the pain of childbirth.
Mike Rostenkowski: Like a woman. Great analogy.

Sheldon: I've changed. Like the frog who's put in a pot of water that's heated so gradually, he doesn't realize he's boiling to death.
Penny: Or you're the frog who's been kissed by the princess and turned into a prince.
Leonard: Or you're just a tall, annoying frog.

Amy: I'm not surprised you want to end the relationship. I'm a little surprised you didn't get AppleCare.