I was reading the script for Harry Potter and the Cursed Child and Fantastic Beasts and Where to Find Them and this made me think about the various fandoms I like. My main ones are Tolkien and Star Wars (before the Disney take-over - I didn't like Force Awakens and probably won't care for the stories that spring off that, but I'm reserving judgement for Rogue One and the various stand alone spin-offs.) Reading those then got me re-visiting Jim Butcher's Dresden Files, and this made me think which, out of all the books, films and TV shows I like, which are the ones which stand out and blow the rest out of the water, so to speak? These are the ones which we are most likely to be inspired to write fan fiction for and create rp games and boards, the ones which seem to get us through times that are tough.
Lord of the Rings/The Hobbit
Women of the Otherworld (includes the adult and YA books)
Mercy Thompson/Alpha and Omega
Star Trek: The Next Generation
Star Trek: Deep Space Nine
Star Trek: Voyager
Buffy the Vampire Slayer/Angel
I wouldn't make an rp site for these books, but they do deserve an honorary mention because they are things I go back to time and again: Watership Down, James Herriot, and One Hundred and One Dalmatians.