Or cat "hotel" as my kids call it
i took two kickin' boxes I got at costco for free to haul all our food:
A glue gun, some cool vintage "looking" fabric from my stash and some fleece for the bed part (from my stash) and turned the boxes into this:
It is by no means perfect, but I really like it. I haven't seen the cats use it much yet but I think I might tie some pom poms or something to the doorways to give then something to bat at.