It's currently stored in a closet somewhere in my house. I usually end up selling my systems once they are one or two generations outdated so I keep the boxes.
We have the box cause we have a few more moves planned before we can settle down and the boxes for our game systems come in handy when packaging them up for moving. We have both Xbox boxes too
I'm keeping all boxes in my basement out of old habit. In case of returns, stores used to want the original box. It's probably 20 years ago that we got a law that said they couldn't demand the box... But I still save 'em as long as I have the product