Leonard: What kind of a person steals another person's car in broad daylight?
Sheldon: What kind of person leaves his keys in the car?
Leonard: I thought we agreed this was all Koothrappali's fault.
Sheldon: You're right. (To Raj) Nice going.

Kripke: You guys ever use any toys?
Sheldon: I do have a model rocket next to my bed.
Kripke: A rocket? You're a freak! I love it!

Sheldon: Some people are otters, some people are rocks.

Sheldon: Oh really, Leonard? Are you going to have another one of your hissy fits?
Leonard: Hissy fits? I have hissy fits?
Sheldon: Yes, and I have a theory why. Because of your lactose intolerance, you switched over to soy milk. Soy contains estrogen-mimicking compounds. I think your morning Cocoa Puffs are turning you into a hysterical woman.

Amy: What if you could find a roommate who was a scientist and already familiar and comfortable with your ways.
Sheldon: That would be ideal. If a person like that existed, I would sign on, no further questions asked.
Amy: Great. Here I am!
Sheldon: Wait. Here who is where?
Amy: Me. Aren't I your perfect roommate?
Sheldon: Um...
Amy: Think about it, Sheldon. I'm not a stranger, we're both intellectually compatible, I'm willing to chauffeur you around town, and your personality quirks, which others find abhorrent and rage-inducing, I find cute as a button. What do you think?
Sheldon: Um.
Amy: Tell me one reason why this isn't a fantastic idea.
Sheldon: Um.
Amy: See? You can't. I'm gonna go see if Leonard's room is big enough for my water bed.
Sheldon: Um.

Sheldon: Leonard, you're being selfish. We need to give you a proper send-off so we'll have closure when you die at sea and crabs eat your face.

Sheldon: See what happens when you let girls play D & D.

Amy: Missed one. Now your wish can't come true.
Sheldon: Lucky for you because I wished you were dead.

Sheldon: I found three bowling pins. Do you juggle these or are you missing seven?
Howard: Juggle.
Sheldon: You health nuts kill me.

Sheldon: Feelings? What am I, a hippie at a love-in?

Amy: I have some exciting news to tell you.
Sheldon: That makes two of us. My new cuticle scissors will be here in one to two business days. ... Come on, one.

Sheldon: If you're hungry, I brought home mutton and coconut milk.
Penny: Why'd you do that? You hate lamb.
Sheldon: I was asking for directions. Apparently there was a communication problem.

Sheldon: My point is we're a couple and I like you for who you are - quirks and all.
Amy: I like you too.
Sheldon: I should hope so. I don't see anybody else banging on this door to put up with your nonsense.
*Amy slams the door on Sheldon*
Sheldon: Not even a goodbye? You see this is the kind of thing that makes people think you're weird. ... Poor kid. She just doesn't see it.

Sheldon: The National Science Foundation wants to give me a substantial grant.
Raj: That's a big deal.
Sheldon: I know. When will this nightmare end?

Sheldon: I hate to pile on the bad news, but I just got a raise.