To say that Myst Online: URU Live has had a rather odd run would be an understatement. The game has proven that it has more lives than a cat and has the ability to adapt an amazing number of ways and it still keeps coming back for more. In 2008, Gametap discontinued service for the game, but Cyan Worlds acquired the rights to title later that year and in December 2008, Cyan Worlds announced that it would make the game's assets open source.
It's been a slow process and many have wondered what happened to the game since that announcement, but developer Cyan Worlds is back in the news and the open source bells are once again ringing. In a recent announcement picked up by Rock, Paper, Shotgun, Cyan Worlds and OpenUru.org jointly announced the open source delivery of the CyanWorlds.com Engine client and 3ds Max plugin, aka Plasma, the engine used to power Myst Online: Uru Live.
Sources:
Rock, Paper, Shotgun
Cyan Worlds Announcement