what's in it for me

get what's coming to one

To experience the consequences of one's actions.

what's cooking

A greeting, similar to how are you?; what's happening?; what's up?; what's new?

what's eating

What is wrong with...? What is the problem with... (somebody)? Inquired regarding somebody who seems upset, worried, angry, etc.

what's eating you

What is annoying or bothering you?

what's going on

An informal greeting.

what's new

The latest developments in a particular situation or a person's life.

what's the beef

Why are you complaining? What are you complaining about?

what's the difference

(rhetorical question) The difference does not matter; so what?