Modifications and Add-Ons

Annihilation
Single player modification which features 8 armor classes, 4 vehicles, 29 weapons, 7 spells, 18 packs, 11 turrets, 22 deployables, and 3 moving dropships.
http://www.annihilation.info/

BigBunny's Scripting Site
Home of BBFavourites and many other scripts made by BigBunny
http://www.planettribes.com/bigbunny/

Bootcamp
Offers map and scripting environment to train for games.
http://bootcamp.toocrooked.com/

Crunchy's Scripting Site
Home of ObjectiveHUD and many other cool scripts
http://www.planettribes.com/crunchy/

HaVoC
Home of the HaVoC mod
http://www.planettribes.com/havoc/

MADHUD Homepage
Home of MADHUD, a addon HUD for PrestoPak
http://www.planettribes.com/madhud/

Mappers Mod
A mod that makes it easier to add new prefab objects into the map editor of tribes
http://www.planettribes.com/zhandri/

Mental Trousers Tribes scripting stuff
Homepage of PrestoPakPlus, and a good starters guide to scripting
http://www.planettribes.com/mt/

NeoTribes - New Missions for Starsiege Tribes
NeoTribes is a source of quality missions (maps) for Starsiege Tribes.
http://www.planettribes.com/neotribes/

Presto's PrestoPack homepage
get PrestoPack, a great addon for tribes for clients and scripters
http://www.planettribes.com/presto/

Scripters Underground
Home of BooHUD, KillCountHud, and many smaller scripts
http://www.planettribes.com/underground/

SixPak
A compilation of the best Tribes scripts
http://www.planettribes.com/sixpak/

Ultra Renegades
Home of the Ultra Renegades 1/2/3 mods
http://www.planettribes.com/ultra/

X-FAB Map Station
A extremely large collection of Tribes maps
http://www.planettribes.com/xfab/