I think these might've been mentioned before, buuuut
Television shows would include Hannibal, Supernatural, Doctor Who, Sherlock, Merlin, Star Trek, and I guess I can throw in LoTR/The Hobbit
Video Games? Silent Hill, OFF, The Elder Scrolls, Mass Effect, Assassin's Creed, Amnesia (includes The Dark Descent and aMfP, mind you), Penumbra, Pokemon and Halo. I think they'd count, even if there isn't a large group constantly posting fan material for a lot of em'.
Anime pluuus a certain webcomic includes Hetalia, Homestuck, Attack on Titan, D.Grey-Man, and Pandora Hearts.