Despite being made of paper, the material is strong enough to make bookshelves, desks, and beds with, all while being lightweight. It's also billed as being "incredibly" easy to assemble, and would be a good option for the tool-challenged out there as it's put together with industrial-strength double sided adhesive strips (although screws and nails can be used on it.)
Most of the furniture is based around various shaped cubes, rectangles, and straight pieces, and it's pretty impressive to browse the website and see all the furniture that can be made with these pieces. Every piece is available in a range of color choices, and the prices are reasonable - individual pieces run from $1.75 (a shelf divider) to $62 (a three shelf bookcase.)
See more configurations and read more about Way Basics on their website.