we're gonna need a bigger boat

I'm working on chapter indexes right now for the AO3, and we got to talking about stories with lots of chapters, which got me looking at ff.net, where I discovered that there are 137 pages of Harry Potter fic of more than 100,000 words. That's a lot of words!

Ten minutes of searching has netted me an HP fic with 181 chapters (it was at 180 a few minutes earlier) and a LOTR fic with 781,467 words (which is the epilogue of a trilogy!).

Now I'm curious - what are the longest stories you've encountered in fandom? What are the longest stories you've actually read?

ETA: 1,036,782 words of Buffy/Faith over three and a half years, with an impressive average of 12,000 words per chapter - that's probably hard to beat. O.O