Starsiege Tribes has been released as a free game. There are two main client downloads for you to pick from:
Download Tribes 1 classic
Download Tribes 1 with HD textures
Dedicated Game Servers
Currently I run a pair of old school Starsiege Tribes servers:
games.rushworx.net:28001 Standard Tribes
games.rushworx.net:28002 Tribes Aerial Combat mod
For detials on Tribes Aerial Combat (TAC) check out tacmod.com and the TAC1 forum
Dedicated Server Setup details
This old site has the goods on hosting a tribes dedicated server.
(link) (mirror)
I run my game servers in linux. Here is the basic launcher script I am currently using to run Tribes dedicated server in wine:
nohup su -c "cd /srv/tribes; export WINEPREFIX='/srv/tribes/.wine'; \
wine /srv/tribes/Tribes.exe +exec rushworx_tac -mod tac -dedicated" \
-s /bin/sh tribes &
I will some day make an init script or something a little smarter like that.