Book:Discworld (Reformed) Vampyres' Diary 2003
One of the splendid miscellany of books about Discworld with no specific novel value, but with background details in that no fan would dream of not knowing, such as the traditions of the the Überwald League of Temperance movement, full lists of members, high days and holidays, and famous dates and bibliographies of the movement.
Follow this link to find out more.