For a Pay to play online game you just have to go back to the old Sierra Network system in the early 90's they had a graphical MMO style game that you had to pay extra to play above and beyond the normally hourly subscription you paid to be online called s The Shadow of Yserbius. There was also Neverwinter Nights on AOL at the same time which cost 6 dollars an hour to play back in 1991.

They are currently working on a similar process to get a unified platform created with Linux to lower the costs in schools. I know they have been working on it the last 2 years but do not know the status of the project currently.