Raj: At least Leonard, Howard and I would have always been friends.
Bernadette: Hey, how come you three never got an apartment together?
Leonard: We talked about it, but Howard was in a pretty serious relationship ... with his mom.

Howard: I lived with her to save money.
Raj: Yeah, you didn't need to buy groceries because you were breast feeding.

Bernadette: So how come you two (Leonard & Raj) didn't move in together?
Leonard: This guy wanted a place of his own because he was sure he was going to be a ladies' man.
Raj: Yeah, I was wrong.

Leonard: He made you his screensaver.
Amy: Oh, wow. I had no idea. He is so into me!

Amy: I'm just really glad you're back.
Sheldon: Me too. I've got a lot of TV to catch up on.

Amy: I missed you.
Sheldon: To quote Han Solo, "I know."
Amy: Did you miss me?
Sheldon: I would have preferred to have you there with me.
Amy: Aww.
Sheldon: Or instead of me.

Amy: Did you hold the baby?
Sheldon: I did.
Amy: And how did it make you feel?
Sheldon: Looking into the blank, innocent eyes of a creature that couldn't begin to comprehend anything I was saying ... basically another day at the office.

Zack: Hey, babe.
Penny: Hey. Did you remember to pay the rent?
Zack: Better. I used the money to buy these magic beans.

Zack: Aw, babe, I peed myself.
Penny: Me, too.

Ira Flatow: This is Science Friday, I'm Ira Flatow. My guest today is responsible for the discovery of the first stable super-heavy element.
Sheldon: Thank you. The university made me come here, I didn't want to. Big fan of the show.

Ira Flatow: Some people in the science community are calling it the wonder blunder.
Sheldon: Who? Give my their names! I bet it's Wolowitz.

Sheldon: Yes, I'd be a physicist with a Nobel Prize in chemistry. Everyone laugh at the circus freak.

Sheldon: I don't need to sit here and take this, Flatow. It's because of bullies like you that everyday more and more Americans are making the switch to television.

Penny: How can you not be happy? You're tall, thin and famous. ... Oh my God, I'm jealous of Sheldon.

Sheldon: But none of you know what this is like. Being celebrated for something you wish you never did.
Penny: You clearly haven't been with me at Mardi Gras.