"Just so you know" is as clique as Passive Aggressive.

A shot put would be more pointed.

Just because I don't know, doesn't meant that you don't know, does it?

Just so you know, it's 6:34, we closed half an hour ago, asshole.

Just so you know, there's an app on your phone that tells you exactly what time the bus gets here.

Just so you know, we can legally sell you beer until 2:30am, what time does your phone say it is?

Just so you know, this is one of the most annoying I,As I've read in a while.

You're the kind of insufferable asshole who can't be given any information without insisting that you already know it, AREN'T you, I,A?

I know right!

I've never met anyone who has introduced this phrase into common lexicon.

They should be punished by death.