Sheldon: Hey, would you like to hear some songs I've rewritten to get children interested in the hard sciences?
Howard: Sure.
Leonard: Really?
Howard: Yeah. I like music. I like science. I like making fun of Sheldon. Hit it!

Howard: You know, I'm really glad you decided to learn Mandarin.
Sheldon: Why?
Howard: Once you're fluent, you'll have a billion more people to annoy instead of me.

Bernadette: Maybe we should get one of those machines to help her up the stairs.
Howard: You mean a forklift?

Sheldon: Sheldon Cooper does not cry.
Howard: That's true, you'd rust.

Sheldon: *singing in the tune of "Eye of the Tiger"* It's the eye of the tiger, it's the ear of the bat. It's the whiskers of a catfish and the walrus--
Howard: Hang on. Not that your song isn't terrible-- it is... but how do you mention bats and leave out sonar?
Sheldon: You didn't let me finish. *singing* And also regarding the bat. It has sonar.

Howard: First take a picture with me.
Bernadette: Why?
Howard: Well, Raj and I always talked about learning how to make cocktails like this together, so I taught myself and I'm putting this on Instagram so he can see it and feel like a turd. Say cheese!

Raj: Okay, so, what it sounds like is, what we want is a device that can deliver a message through not only sight, but other senses, as well.
Leonard: The most basic sense that any space-faring civilization would have to possess is touch.
Raj: Ooh. Ooh, ooh! We could make a video-playing device that simultaneously translates the information into a tactile medium.
Leonard: All we have to do is rig up a 3-D communication system!
Raj: We-we can totally do that!
Leonard: I know!
Raj: This is great!
Leonard: Yeah, you know what else it is?
Raj: What?
Leonard: Exactly what Sheldon and Howard said.
Raj: Well, thank you for peeing in my slippers.