Rajesh: Excuse me but I don't think Penny is out of line at all. You don't own her. It's like my girl Beyonce says: If you like it you should've put a ring on it.

Sheldon: There there, everything is going to be fine... Sheldon's here!

Sheldon: You did this, didn't you?
Wil Wheaton: Come on, Sheldon, do you really think I'd break up a couple just to win a bowling game?
Sheldon: No, I suppose not.
Wil Wheaton: Good. Keep thinking that.
Sheldon: Wheeeeatoooon!

Penny: I always tear up when the Grinch's heart grows three sizes.
Sheldon: Tears seem appropriate. Enlargement of the heart muscle, or hypertrophic cardiomyopathy, is a serious disease which can lead to congestive heart failure.

Penny: Sheldon, did you have a Christmas tree?
Sheldon: Oh, yes. We had a tree, we had a manger, we had an inflatable Santa Claus with plastic reindeer on the front lawn. And to make things even more jolly, there were so many blinking lights on the house they induced neighborhood-wide seizures.

Sheldon: There's a fine line between wrong and visionary. Unfortunately, you have to be a visionary to see it.

Sheldon: Where's the ring?
Leonard: It's in a Fedex box on its way back to where it came from.
Raj: The fires of Mount Doom?

Sheldon: I recently had a dream that I was a giant. But everything around me was to scale so it all looked normal.
Leonard: Well, how did you know you were a giant if everything was to scale?
Sheldon: I was wearing size a million pants.

*After getting a spare in the bowling match*
Sheldon: Thank you, Jesus! As my mother would say.

Howard: Wazzup, my nerdizzles?

Leonard: You know what, go to Hell and set their thermostat.
Sheldon: I don't have to go to Hell. At 73 degrees, I'm there already!

Wil Wheaton: What's wrong with him?
Stuart: Everybody has a different theory.

(Sheldon notices Penny taking Leonard to his bedroom)
Sheldon: What's going on?
Penny: Get your noise-cancelling headphones, 'cause it's gonna get loud.
Sheldon: Oh, not this again.

Leonard: Can I have a napkin.
Sheldon: I'm sorry, no!
Leonard: But you have a whole bunch of napkins.
Sheldon: Yes, I've moved to a four napkin system, lap, hands, face, and personal emergency. If you like, starting tomorrow, I'll add a guest napkin but I'm afraid there's nothing I can do for you today.
*Leonard grabs a napkin.*
Sheldon: Good luck, that's the face napkin.

Beverly Hofstadter: So, Howard, have you and Rajesh finally summoned the courage to express your latent homosexual feelings towards one another?