I really wish I could find a service like this, with dead simple Markdown-based publishing and a minimalist interface, but that also supported anonymous paragraph-level commenting. It's something that would be perfect for the tabletop gaming community, which right now has a heavy bias towards Google Docs for public drafts almost entirely for the easy commenting on specific sections of text.

Medium used to seem like it could fill that role, but then they moved towards being as annoying as possible to logged-out users.