Sheldon: Greetings, friends.
Leonard: (To Robot Sheldon) Greetings, whatever-the-hell you are.

Sheldon: There's a lot of harm in trying something new. That's why we test out drugs and cosmetics on bunny rabbits.

Leonard: Sheldon, would you be prepared on a non-presidential basis, to create an emergency ad-hoc slurpee/icee equivalency?
Sheldon: Oh Leonard, you know I can't do that.

Howard: You should've seen the look on your face!
Sheldon: Oh, yes. The slightly widened eyes of mildly startled.

Sheldon: I was going to name him Hermann von Helmholtz, but he's so zazzy.

Penny: Okay, that's fine, but let's try and get you out of your comfort zone.
Sheldon: Why would we want to do that? It's called the comfort zone for a reason.

Penny: Okay, I got a box, but there's no key in here. Just letters.
Sheldon: That's the wrong box. Put it back.
Penny: Oh, Sheldon, are these letters from your grandmother?
Sheldon: Don't read those letters.
Penny: Oh, look, she calls you Moon Pie. That is so cute.
Sheldon: (shrieking) Put down the letters!

Sheldon: Leonard, let me tell you something. Personal robots cannot get here soon enough.

Leonard: We had a vote. Three of us voted for airplane. Sheldon voted for train, so we're taking the train.
Sheldon: Don't say it like that, Leonard. Say it like, "We're taking the train!"

Sheldon: I'd like to have a talk about relationships.
Raj: You were supposed to have the talk with him.

Sheldon: You are soft. The world is going to chew you up and spit you out.

Sheldon: I don't watch you twenty-four hours a day. I don't know what you do.

Sheldon: Leonard, I platonically love you, man, but face it, you're a mess.

Sheldon: I'm not going to say I told you so, but we could have killed him.

Leonard: Do you think we can outrun him?
Sheldon: I don't need to outrun him, I just need to outrun you.