Image via Wikipedia
There's no way to save cancelled or dead MMOs like Auto Assault or Tabula Rasa for posterity. This is partly due to the fact that the Ip holders won't release them for emulation, but that's not the only problem. Consider that a lot of the servers are made to run on specific hardware, so a common emulation platform is likely to yield less than optimal results. even if you get them emulated and running, but the resulting playerless game experience match what really happened when these games are live?
Music, theater and movies they have the benefit of being recordable -- hell, even console games can be copied and preserved -- but online games are ephemeral. Even if you preserve the content, you'll never really capture the experience (well I suppose an empty server actually pretty well captures both AA and TR, sadly) and isn't that sort of sad?
Who's going to remember Auto Assault? beyond it's tiny and umremarkable wikipedia entry? Who's going to remember the effort that everyone put into those games? Will anyone remember how brilliant and unrecognized neocron was, for its time? I know it probably sounds like a pretty minor thing to most folks, but the idea makes me very, very sad.