The Internet suggests that slumber party guests often engage in harmless experimentation with lesbianism.

Amy

I believe I'll gain acceptance by arbitrarily siding with your friends from time to time.

Amy

Even at Star Trek conventions, they only let him in if he helps set up!

Sheldon [about Wil Wheaton]

Gee, I don't know if I should drink more. I have to drive home and I've got enough trouble seeing over the dashboard as it is.

Bernadette

Well, if it isn't Wil Wheaton, the Jar-Jar Binks of the "Star Trek" universe.

Sheldon

Sheldon: And here's where we are -- the runts in a large litter unlikely to ever reach the nourishing teats of Indiana Jones.
Leonard: So it's good we stopped for dinner.

Penny: Okay, help me out here. How does an archeology professor get that good with a whip?
Wolowtiz: Maybe he took a class at the adult book store. That's how I learned.

I'm guessing 21 seconds had something to do with that, too.

Wolowitz

I find zombies dancing in choreographed synchronicity implausible. And also it's really scary.

Sheldon

No, Gorn, no! That's where I sit.

Sheldon

Please don't send me back to India! It's so crowded. It's like the whole country is one endless Comic-Con, except everyone's wearing the same costume -- Indian Guy.

Raj

Leonard: Hi. I'm Leonard. You are beautiful. You pop, sparkle and buzz electric. I'm going to pick you up at eight, show you a night you will never forget.
Raj: Where are we going?

TBBT Quotes

Oh, Bernadette, please play my clarinet.

Raj's poem

Sheldon: I'll have a diet Coke.
Penny: Can you please order a cocktail? I need to practice mixing drinks.
Sheldon: Fine... I'll have a virgin Cuba Libre.
Penny: That's... rum and Coke without the rum.
Sheldon: Yes, and would you make it diet?