Thunky loves his shelves and we decided to build some more. A month or so ago we put a lower shelf above the kennel for him to get up there instead of using the treadmill. He loved that so we figured another place for him to get up there should be our next goal and he likes to get on my computer desk. There is over 30 feet of cat shelving now and he tears around it and sleeps in his hammock all the time. More pics and a video here.
The carpet squares box is fun too.