Penny: Mustache is looking good there, Sheldon.
Sheldon: Don't thank me. Thank the dice. They told me what percentage of my face to shave.
Howard: Why are you still doing this?
Sheldon: Because it's working. In the past few weeks, unburdened by trivial decisions, I've co-authored two papers in notable peer-reviewed journals, and I'm close to figuring out why the Large Hadron Collider has yet to isolate the Higgs boson particle.
Leonard: You left out, got chafed testicles because you no longer wear underpants.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Penny: (Whispers) Here she comes.
Howard: Smart. Whisper so the deaf chick doesn't hear you!

Sheldon: The entrance to the dungeon is a moss covered door. You manage to open it only to find yourself face-to-face with a hideous, foul-smelling, moss-covered ogre. What do you do?
Howard: I say, "Hey Ma, what's for dinner?"

Raj: I don't know if I wanna play any more.
Sheldon: Because you don't have a girlfriend? Well, good lord, if that becomes a reason to not play dungeons and dragons, this game is in serious trouble.