Sheldon: Hello, Penny! Leonard just left.
Penny: I know. I wanna talk to you.
Sheldon: What would we talk about? We have no overlapping areas of interest, as I'm aware of. And you know I don't care for chit-chat.
Penny: Can you just let me in?
Sheldon: Well, OK but I don't see this as a promising endeavor.

Sheldon: I'm no stanger to mimetic epidemiology. At Johnson Elementary school, the phrase Shelly Cooper's a smelly pooper spread like wildfire.
Amy: I should think so, that's gold.

Sheldon: Oh, mimicry. I enjoy mimicry. I've been working on Admiral Ackbar from Return of the Jedi. "It's a trap". You have to imagine me with a giant squid head. "It's a trap! It's a trap. It's a trap."

Sheldon: I refuse to sink to his level.
Raj: You can't sink, with all that helium in you, you're lucky you don't flow away.

Sheldon: Raj! What are you doing?
Raj: *raises coffee cup*
Sheldon: I don't think so. You've already had your allotted 6 ounces. The next bathroom break isn't until the Denny's near Bakersfield, which is approximately 2 and a half hours away. Remember people, we're only as strong as our weakest bladder.

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

Sheldon: I want you to tell me that Howard is being mean to me for no reason.
Penny: Fine, Howard is being mean to you for no reason.
Sheldon: I knew it!

Sheldon: (blows nose into tissue, shows family sitting at nearby table) Would you call that moss green or forest green?

Sheldon: That's my parking spot.
Raj: Why do you have a parking spot? You don't have a car. You don't even drive.
Leonard: Maybe they reassigned it because you never use it.
Sheldon: Well, I'm not using my nipples either. Maybe they should reassign those.

Sheldon: Well, that stinks. No wonder you got cancelled. Bye.

Sheldon: I think I've come up with the perfect way for us to enjoy it.
Penny: Great. How?
Sheldon: We pretend we're aliens. We pretend we're aliens. I'm not the best at reading facial cues, but I'm gonna say that you love it and wanna hear more.

Raj: Amy, that pudding was delicious.
Sheldon: If you like raisins.
Amy: Thank you. And it's figs.
Sheldon: Oh. In that case, it was pretty good.

Leonard: This isn't so bad.
Sheldon: That's easy for you to say. Your chair isn't facing the lingerie section. Boy that's a lot of panties.

Sheldon: You're mean to me a lot. You think I don't notice all those sarcastic comments and those eye rolls, but I do. I have excellent peripheral vision. On a good day, I can see my ears.

Amy: Have a seat on the floor.
Sheldon: Not there. That's my spot.