Create modular cat houses with these carboard building blocks

A Cat Thing combined feline love for cardboard boxes with an architect's eye for modular prefab housing to create a series of max-and-match cat houses.

Via their site:

There are four different modules: room, living room, balcony and ramp. Their modular nature makes them easy to assemble. You can create the most suitable structure according to your available space and your cat's personality.
Except being a secret compound to play and rest, this cat house is also part of your interior design. It brings a very natural and warm texture to your living space.

A Cat Thing (via Designboom)