In my opinion, the following is the coolest one.  It’s in a private home.  Specifically, the home of Jay Walker.  Funny name.  Awesome library!

Nothing quite prepares you for the culture shock of Jay Walker’s library. You exit the austere parlor of his New England home and pass through a hallway into the bibliographic equivalent of a Disney ride. Stuffed with landmark tomes and eye-grabbing historical objects—on the walls, on tables, standing on the floor—the room occupies about 3,600 square feet on three mazelike levels. Is that a Sputnik? (Yes.) Hey, those books appear to be bound in rubies. (They are.) Gee, that chandelier looks like the one in the James Bond flick Die Another Day. (Because it is.) No matter where you turn in this ziggurat, another treasure beckons you—a 1665 Bills of Mortality chronicle of London (you can track plague fatalities by week), the instruction manual for the Saturn V rocket (which launched the Apollo 11 capsule to the moon), a framed napkin from 1943 on which Franklin D. Roosevelt outlined his plan to win World War II. In no time, your mind is stretched like hot taffy.

Reading Room In the foreground are several early-20th-century volumes with jeweled bindings—gold, rubies, and diamonds—crafted by the legendary firm Sangorski & Sutcliffe. On the table (first row, from left) is a 16th-century book of jousting, a Dickens novel decorated with the author’s portrait, and (open, with Post-it flags) an original copy of the 1493 Nuremberg Chronicle, the first illustrated history book. Second row: the 1535 Coverdale Bible (the first completely translated into modern English), a medieval tome with intricate illustrations of dwarfs, a collection of portraits commissioned at a 17th-century German festival (“Facebook in 1610!”), a tree-bark Indonesian guide to cannibalism, and a Middle Eastern mother goddess icon from around 5000 BC.

Gadget Lab A brand-new One Laptop per Child XO, far left, sits next to a relatively ancient RadioShack TRS-80 Model 100. In back, a 1911 typewriting machine and a 1909 Kent radio. The large contraption at center is the Nazis’ supposedly unbreakable Enigma code machine. The book to its left is a copy of Johannes Trithemius’ 1518 Polygraphiae, a cryptographic landmark. On the right is an Apple II motherboard signed by Woz. An Edison kinetoscope sits beside an 1890 Edison phonograph (along with three of the wax cylinders it uses for recording). Nearby is a faithful copy of Edison’s lightbulb. The gadget with the tubes is an IBM processor circa 1960. In front of it stands a truly ancient storage device, a Sumerian clay cone used to record surplus grain.

See more of Walker’s library here.