Leonard: I'm sorry. The bride and groom seem happy.
Amy: Why shouldn't they be? They have a feverish night of socially-approved copulation ahead of them. In some cultures, we'd stand outside of their bedroom cheering as they achieved orgasm.
Leonard: That sounds like a late night, and I have work in the morning, so...

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.

Amy: The only person who signed my yearbook was my mother. "Dear Amy, self respect and a hymen are far better than friends and fun. Love, mom."

Bernadette: Good Morning, handsome.
Howard: Good morning, mom.
Bernadette: It's me!

Amy: I have a sorta kinda boyfriend at home playing with a model train, but you don't hear me bitching about it.