I can't think right now, but here are a few things I say way too often:

suboptimal/less than ideal/nonstandard: Used to describe something that is/was truly idiotic to do/say.
Umm... No.: Used for emphatic disagreement.
Whatup, whatup.: I stole this from my uncle. He uses it essentially every time he walks into a room with people in it.
Why would I want to do that?: Self-explanatory

I'm sure there are more...