Well, at least Hellgate: London has the offline, single play version of it... So even if or when the servers finally shut down, people who bought the game can continue to play, although in a limited form.. I know I made sure to get the latest updates, even if most of the updates were for the online version.

Sadly, no such thing for Mythos. I can only hope that the creators manage to deal with the legal issues and retain the game, so they can continue to develop it at a later date. It's to nice a game to die before it really had a chance to really live.