And then there's Fallout:Equestria. 2034 pages, 608,000 words. It's a good story. Not great, certainly no Harlan Ellison, but better than, say RA Salvatore or Thomas M. Reid.
http://maximillianveers.deviantart.com/art/Fallout-Equestria-eReader-215378302? has the pdf.
http://maximillianveers.deviantart.com/art/Fallout-Equestria-eReader-215378302? has the pdf.