As noted on his official home page, science fiction and fantasy author Philip José Farmer died yesterday at the age of 91. Farmer was an influence on the development of Dungeons & Dragons primarily through his "World of Tiers" series, which Gary Gygax cited in Appendix N of the AD&D Dungeons Masters Guide. Of course, Farmer was incredibly prolific and wrote many, many short stories and novels -- a career stretching back to the 1940s -- making it next to impossible to limit his influence on and inspiration to the hobby to a single book or series of books.
For myself, it was Farmer's frequent use of pulp heroes and heroines that endeared his writings to me. His magnificent "Wold Newton family" is an amazing work of creativity, an attempt to connect -- and, on some level, rationalize -- the lives and adventures of numerous beloved characters ranging from Sherlock Holmes to Doc Savage to Solomon Kane. Farmer demonstrated that same level of inventiveness (and cheekiness) in most of his works and he will be sorely missed by his legions of fans.
May he rest in peace.