Pewey Decimal System
The Pewey Decimal System is a tool for sorting knowledge of various kinds. Due in part to the inclusion of magical writings and spells, the system has gathered a magical quality of its own. It is employed in the Floating Library and other libraries throughout the continent. Familiarity with the system requires at least 4 ranks in various knowledges and a trip to any library that employs it. The inventor of the system and it's name sake is Melville Pewey. There are feats associated with the system, Sociable Librarian, Knowledge Devotion, and Law Devotion.
Any character within a library that utilizes the Pewey Decimal System may use the library as a masterwork tool when making knowledge checks. They may also employ a librarian to gain an aid another bonus to knowledge checks in a library that uses such a system. The librarian may charge the PC based on the DM's digression.