IDK if it can be considered high quality, but the fanfic that got me really involved in fandom was Cassandra Claire's Draco Trilogy. I think it's a really interesting one 2 look @ becuz it's so controversial (there are a lot of haters due 2 copyright issue

Awesome thank you! My project is all about the grey area between copy write and the sharing of fic for the love of creating new narratives so this is super exactly what I want to know more about.