Fan fiction, some of it heartbreakingly brilliant, some of it so badly written you wonder if they ever even saw the original series. But glued to their devices they tap out their allegiance to people or beings who are imaginary. -- Anon Guest
The Archive of Transformative Works is a subset of the Archivaas Conglomerate. Those who strive to preserve everything humanity or intelligent life has created. Even the worst that a barely creative mind has to offer. It is oppressively huge. Its collection is daunting. And a few luckless souls have attempted to figure out rules.
If it exists, there is porn of it. The erotica section is almost a planet in and of itself. Broken into subsections according to the relevant options. It is best for novices not to explore these cavernous shelves. Some things in there are only for an experienced or open mind to see.
There is always a coffeeshop AU. If the original is set in a coffeeshop, then the AU will be about flower shops, book shops, or set in a high school. These are far more palatable, but almost formulaic in their execution. The potential for crossovers is abundant, and cross-referencing is a vital duty for the acolytes.