The luxury Library Hotel in Manhattan has rooms based on the Dewey Decimal system. For example "[r]oom 700.003 includes books on the performing arts, for example, while room 800.001 has a collection of erotic literature." However, the owners of the Dewey Decimal system are not amused and are suing the hotel for trademark infringement. Based on the hotel website, it looks like a pretty nice place to stay. Here's a full list of the rooms available. (Via IPList.)