Pathfinder Homebrew as MMO?
Well, I play on a Pathfinder MU*. :)
They've a group of dedicated GMs, as well, players can run scenes on their own. The adventures are generally split into several groupings: levels 2-5, 6-10, 11-14 and 15+. There are occasionally events for all level groups.
Basic roleplay can be logged and posted to earn RPP (roleplay points), which can be used to buy a variety of character things: a level, a player run shop, a house, membership in an exclusive group (like a thieve's guild, the Harpers, the Pathfinder Society, etc.), and quite a few others. I believe submitting an RPP post also earns you a bit of money and XP also.
Players can +nom other characters, which gives those characters some XP. You can nom for roleplay or in events and so on.
Events are GM run (or player run with GM assistance), where you can earn XP and gold and magical items.
It takes quite a bit of work to have it running smoothly, and it requires a lot of buy-in from the players. But it runs pretty well.