Subspace went through over 30 revisions during testing, most of which were released for open beta. Open beta testing continued for almost 2 YEARS, building one of the most fanatical user groups in the history of gaming.
When Subspace was finally released, it shipped with both client and server software, guaranteeing that Subspace would exist long after the company stopped supporting it. This happened in late 1998, but player-run servers still exist, with a large contigent of players.
Unlike many other multiplayer-only games, Subspace never charged a monthly fee.