Tribes
the original
Orb was founded in Tribes as well as contributed to several of the game's several widely used mods such as Annhilation, Tribes RPG, and Shifter. There is not a lot of servers still online, but the game is freeware and available to all to download and play.
Download
Note: Since tribes0.com has gone down, I am searching for updated archives of these files.
114 MB - Bugs fixed and 1.41 patch by The Community
Game set 1.40v by GarageGames
349 MB - High Quality Textures and Interface.
Game set released by FSB-SPY
134 MB - Tribes RPG Starter pack
For Particle's Custom RPG. more info
Tribes 1 Realtime Master Server List
Establishing uplink with satellite network...
Links
Please note - Tribes is a game from 1998, many of these sites will fade away over time. I've attempted to keep as many links to old resources here as possible.