REK is composed of five interlocking components that can be compressed or expanded as needed. Whether you want to store a dozen or a hundred books, you don't have to have any excess shelf space or take up a full wall of your house with an empty bookcase. It's an ingenious idea and might be worth owning for the sake of beauty and novelty alone, but ultimately efficiency of space clearly isn't the true goal here; the shelves and walls are so thick and numerous as to neutralize any real space-saving advantage.

Sang Hoon Kim Curved Bookcase

Empty, this bookcase looks like a diagram of curved space from a theoretical physics textbook. Very cool. Filling it with books might present a few problems though. It won't fit snugly against any wall and there is no back to push your books against, which could certainly lead to a few strays falling into the crevice next to the wall. Still, Kim's design is striking and playful--- and this one seems pretty primitive alongside some of his other work.

Obo Shelving by Jeff Miller

Jeff Miller's Obo modular shelving units are a great way to commune with your inner Lego man. Modular storage has always been a forward idea--- we very rarely buy storage for things (in this case books) that we're going to buy, just what we already have. Being able to reconfigure your bookshelf as new treasures are added to your collection each month is liberating from an interior design perspective. The modules come in seven color options and are sturdy enough to be stacked pretty much as high as you could want them.

FlexiTube Modular Shelving

Another modular shelving product, this time in a form reminiscent of stacked bubbles. Perhaps the most fun aspect of this design is the illusion it creates--- spheres won't stack like this unless they're constrained at the base. The "stopper" for this piece is so subtle the eye misses it until you realize that it must be there (additional support comes from the frictional tension provided by the spheres' fabric exteriors. Sure you could cover a wall in these, but they're also a great way to break up large narrow spaces.