As I've written about before, we've included some kitty-friendly features in our addition. We were inspired in part by The Cats' House, but we'd never go that far (we say repeatedly to reassure ourselves.) Well, someone else would. They've done their own Cats' House in a sleek, modern style in Japan. TreeHugger considers it wretched excess, though besides the heavy-duty grill to fence in the balconies (which is good for preventing your little darlings from decimating the local bird population), the incremental cost for the various steps and shelves is very low and isn't taking extra space. I don't read Japanese to know all the particulars, but it hardly seems wretchedly excessive or un-green to me. Maybe the house is 50% bigger just for the cats? And lest the goggehs...er...doggies feel left out, the same builder has a house full of dog-friendly features, too.