Jay Walker is an American entrepreneur and inventor (he founded priceline.com and holds more than 250 U.S. patents) who has used his massive wealth to create an astonishing private library in his Connecticut mansion. Walker’s Library of Human Imagination contains more than 50,000 volumes and hundreds of museum quality displays. The library’s architectural plan was inspired by M.C. Escher artwork.

Unfortunately, the only way to visit the library is by personal invitation. mine appears to have been lost in the mail. But you can still watch a cool TED talk by Jay Walker.