Bigger is usually better, but sometimes a room just can't accommodate a monster shelving unit. Fortunately, designers have crafted some skinny alternatives to maximize space. Here's a roundup of some of the stack-based shelving out there.
Array Bookcase; CB2; $189; available in orange or aluminum
Stak Bookshelf; top3 by design; $780-$910 AUD; available in grey and white, two sizes
Talma Vertical 7-Tier Book Case; Nexxt by Linea; $130; available in java or black
Spine Book Tower; SEI; $110
Ptolomeo Book Stand; Conran; $2,100; also available in 63" (84.5" model shown)
Sapien Bookcase; Design Within Reach; $198-$298; available in tall or short
Spine Wood Bookcase; West Elm; $179; currently available in chocolate or white