Dungeons and Dragons Online is enjoying a second life in terms of player count and buzz, all thanks to a new business strategy: giving the game away. Turbine is making their MMO as accessible as possible, and that includes making players who don't pay anything as happy as possible. Subscriptions are up 40 percent. Ars explores how free can be very profitable.

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By giving away the game and much of the content, players are up, more people are subscribing, and the buzz around the game has never been stronger. Will we see this model replicated? More than likely. For now though, Paiz has invited me to jump onto the server to see what all the fuss is about. Why not? I have nothing to lose.
http://arstechnica.com/gaming/news/2009/10/ddo-free-to-play.ars