Black Gold Online's payment model might well be one of the most convoluted and bizarre plans ever instituted in an MMO -- and it's coming soon to the North American continent. Identical to the model that's being used in China, Black Gold's NA payment plan alleges to bypass subscriptions and cash shops entirely.
How? Well, it's not explained very well, but that could just be because this monetization model was obviously crafted by a lawyer who hates gamers. The gist of it is that you won't be getting your good loot when you play; instead, your loot will go into a "save file" for optional cash purchase later on. The system holds back rare materials and premium equipment, giving you the chance to purchase the past one, two, four, or six hours of accumulated goods. You can also gamble to try to lower the cost of the purchased save.
Snail Games Founder Shi Hai thinks this plan is just peachy: "We're focusing on giving our players choices when it comes to their gameplay experiences -- they decide what premium items to pay for and whether a play session is worth saving."
[Thanks to Paul for the tip!]