There's a thread outlining setup, costs and performance of running a MC server on the amazon "cloud" platform.
http://www.minecraftforum.net/viewtopic ... 10&t=41077
Don't know how/if we could do that with such a big playerbase though.
http://www.minecraftforum.net/viewtopic ... 10&t=41077
Don't know how/if we could do that with such a big playerbase though.