Bloxes, pl. n, ˈbläks-es Building blocks made of interlocking pieces of corrugated
cardboard, folded together. Their unique shape and structure make them
exceptionally strong and lightweight — you could build yourself a
platform to stand on, and then pick it up and move it wherever you need
to.
From CNET: “Bloxes are the latest option in cardboard furniture,
which is gaining a toehold in the world of ‘green’ design. The
corrugated cardboard puzzle pieces lock together to form sturdy shapes
such as chairs, walls, and play forts.”