I just realized that I seldom write/read fanfiction of books, and when I do, it's because they've been adapted to multi-media. Like, when I was into the LoTR and Hobbit fandoms, my baseline was the movies. When I got into Hannibal, it was because of the TV show. Harry Potter--the recent video game. Even my most recent story, set in the Song of Ice and Fire, is based on the series.
The only time I've had the book-version in mind, was when I was looking for stories on Arya/Jaqen H'ghar.
Everything else, I imagined the assets and events used in the shows/movies.
It's the same with drawn media. Manga and comic books don't inspire the urge for fanfiction in me, but anime and movies do. I had no interest in reading Marvel fanfiction until the movies came out. I only got interested in fanfiction for Haikyuu, One Punch Man and Chainsaw Man when I saw the anime.
The type of media I tend to write for is video games and the ones I read from are TV shows. I have no idea why, but I just thought it was interesting how certain media can make my brain latch onto the IP more creatively than others.
How about you guys? Any media preferences as well or maybe you have other factors in play?
Oh gosh, I think it's less media-specific for the media's sake, and more about what medium I'm currently invested in. On an anime kick? I'm reading anime fan-fiction. Obsessed with a video game? It's all game-verse. Etc.
Is there a medium you don't really touch even if you're on a binge? Like for me, it would be books. Or are you an equal-opportunity fanfiction consumer?
Hmm... maybe epic poetry, podcast, or song? I don't think any of those have ever inspired any kind of desire to write fic. The medium has to give me more of a sense of attachment to the characters I'm likely to write about. I have never felt compelled to write a fanfic for Beowulf, for example. And in Beowulf's case, the movie was somehow worse than the poem. >_<