Reiner De Jong of Rotterdam (where they have much cooler names) pushes the limits of what furniture can do with his REK series. So far, there are only two pieces in the line, but they're both beautifully designed and totally malleable constructions.
The REK coffee table, which operates a bit like a wide, truncated Jenga tower, looks to be about the same size and shape as your average living room surface when in its dormant state. Pull out the slabs from its center, though, and suddenly you find yourself with a much higher table space to floor space ratio. You can pull out the table's pieces in multiple directions, allowing for a little creativity in how you arrange your coffee cups and novelty books on any given day. The REK looks as though it'd be perfect for folks who have somewhat limited living room square footage (or at least who like the look of a small coffee table most of the time), but still like to have guests over from time to time. It folds up to a non-obtrusive size for daily purposes, but then unfolds to house comfortably all the drinks and comestibles of your visitors.
The complementary piece in the same line, the REK bookcase, takes the same concept and applies it to your literary storage needs. Compressed completely, it's not much of a bookcase at all. It resembles more of a long, vertical maze. But start to pull its pieces apart and it reveals its book-storing compartments. The concept behind the piece is that it grows with your book collection, so you never have those awkward empty spaces emphasizing how poorly read you must be. With a snugly-fitting case, your literary accumulations will seem substantial no matter their actual size. It's also a nifty-looking stick of furniture, taking unexpected turns along its length like an overfull Tron screen. Much more interesting to look at than your standard Excel-style case.
Being that the REK line is designer furniture from the Netherlands, it's going to set you back quite a few Euros if you decide your living room absolutely needs it. But maybe we'll soon see this design concept make its way over to the states for less.