Creative agency Nothing in Amsterdam wanted to make their entire office a "blank slate" so they built it out of cardboard. The desks, chairs, shelves, cubicles, and from the photos, even steps and a small loft is constructed entirely of brown cardboard, which invites lots of cool drawings. The Nothing web site explains:
The idea being, to create an office that will turn our clients into brand advocates, by using the most Nothing-building material we could find. At the same time, have the walls double as a blank canvas, on which people can leave their mark.
Here are a few photos of the cubicles and cool drawings:
This reminds me of Aza Raskin's neat Bloxes product, the modular cardboard building blocks that let you create dividers, walls, and even (big and unwieldy but fun) chairs. Also, whiteboard paint and Chris Martin's piano scribblings.