Howard: Easy. Instead of saying; 'No we don't wanna go on an NSF expedition,' say; 'No we don't wanna spend three months stuck in a cabin in the Arctic Circle with an anal nutbag!'

Beverly Hofstadter: It might explain why the two of you have created an ersatz homosexual marriage to satisfy your need for intimacy.
Howard: Say what?

Wolowitz: If it's "creepy" to use the Internet, military satellites, and robot aircraft to find a house full of gorgeous young models so I can drop in on them unexpected, then fine, I'm "creepy".

Wolowitz: They're called tattoo sleeves. Put them on, have freaky sex with some freaky girl with her business pierced, take them off, and I can still be buried in a Jewish cemetery.

Wolowitz: Yes, she's pushy, and yes, he's whipped, but that's not the expression.

Howard: Hey, you want to make sure he gets nowhere with Penny without jeopardizing your friendship with either of them?
Leonard: I'm listening.
Howard: Just tell him to do everything you've done with her for the last two years.

Leonard: Howard, this is big science. You could be the engineer who builds the equipment that puts us on the cover of magazines.
Howard: I could also be the engineer who builds the crossbow that kills Sheldon.

Raj: Is this just so we won't touch your stuff while you're away?
Sheldon: I'll admit that was a concern, but the fact is I'll need a support team, and the three of you are my first choice.
Howard: Really?
Sheldon: Well, there are others who might be more qualified, but the thought of interviewing them gave me a stomach ache.

Howard: Sheldon, you remember the first few weeks we were looking for magnetic monopoles and not finding anything, and you were acting like an obnoxious, giant dictator?
Raj: I thought we were going to be gentle with him.
Howard: That's why I added the '-tator'.

Raj: What do you say, Howard?
Howard: I say Vegas baby!
Raj: What are you gonna tell your mother?
Howard: Sea World baby!

Wolowitz: Raj, there's no place for truth on the Internet.

Wolowitz: I'm a horny engineer, Leonard. I never joke about math or sex.

Wolowitz: Penny, let me take this opportunity to point out that you are looking particularly ravishing today.
Penny: Not with a thousand condoms, Howard.
Wolowitz: So there is a number.

Sheldon: Camouflaging bald spots. That's primarily a male concern. Perhaps we could expand our market.
Penny: How are flower barrettes going to appeal to men?
Wolowitz: We add Bluetooth.

(Sheldon smiles in a grotesque way).
Howard: Oh crap that's terrifying.