so maybe I'm sentimental, but the old archives hold up. The Gossamer site is still online and it's like walking through a museum—tons of stories from the '90s where the tech is hilariously dated but the angst is timeless. That said, I'm not convinced the 'best' stuff is all clustered on one modern platform. AO3 obviously has volume, but the sheer number of tags can bury the truly great character studies under a mountain of tropes.
My weird tip? Search for authors who wrote during the original run and see if they cross-posted to newer sites. A lot of them did, bringing that grounded, pre-movie-season-series-finale-disappointment energy. The characterization feels sharper, less influenced by later retcons. Sometimes the best finds are in the comments of old LiveJournal communities, where someone will link to a personal site that's still up.
I just reread a Mulder/Scully slow burn from 1998 last week that had better tension than most novels on my shelf. So maybe 'best' is less about where you look and more about when the story was written.
I'm always struck by how often Mulder and Scully end up in 'Supernatural.' It's almost a rite of passage. The shared monster-of-the-week structure makes it seamless, but the real draw is throwing the ultimate skeptics into a world where the rules are openly supernatural. Watching Scully try to rationalize a ghost Sam and Dean are exorcising, or Mulder getting way too excited about a real vampire, writes itself. It's less about the lore crossover and more about that brilliant culture clash between FBI procedure and the Winchesters' 'salt and burn' method.
Another big one I've seen is with 'Twin Peaks.' Both shows have that core weirdness buried in small-town America, and the FBI connection is a natural bridge. A plot where Mulder gets obsessed with the Black Lodge while Scully tries to pin down a logical explanation for Laura Palmer's death just fits. The tone matches perfectly—that eerie, slow-burn mystery with a hint of cosmic horror. Those stories often lean into the psychological thriller side more than the sci-fi.
Weird thing is, I drifted away from 'X-Files' fic for years then came back and the landscape shifted. Instead of just UST and monster-of-week AUs, there's this whole subgenre now that treats their dynamic like a decades-long archaeological dig. Saw one recently set in 2015 where a retired Scully finds Mulder's old field notes with little doodles of her in the margins from 1993, and the whole story is her piecing together his side of their early years through these artifacts. It's less about will-they-won't-they and more about the sheer weight of shared history, the ways they documented each other even when they couldn't articulate it.
That approach feels truer to the show's later seasons to me. The fic that sticks now acknowledges the baggage—the loss, the lies, the institutional betrayal—but uses it as texture rather than just angst fodder. Their dynamic becomes about two people who have the same reference points for 'weird' and 'traumatic,' which is its own form of intimacy. You can't replicate that with any other pairing.
Archive of Our Own is basically the main hub for it now. I check there almost daily and new Mulder/Scully fics pop up constantly, plus a surprising amount of Krycek-centric stuff and monster-of-the-week episode tags. The tagging system is a lifesaver for finding post-revival seasons 10-11 content or sticking to the classic 90s vibe.
For a more curated, almost museum-like feel, sometimes I wander over to Gossamer. It's an old-school dedicated X-Files archive, so updates are slower, but the stories there feel like they have a different texture—authors who've been writing since the show first aired. You won't find the latest speculative fic about a new season there, but the depth on characters like the Lone Gunmen is unmatched.
My weird little tip is to search the X-Files tag on Dreamwidth. A lot of writers use it as a blogging platform to post snippets, headcanons, and link to their AO3 works, and the community circles there often signal-boost new stories you might miss otherwise.