R.E.A.R.M. - "Rearmament Expansion And Redesign Mod" is an unofficial Homeworld 2 expansion and it adds number of new interesting and various units.
This is the mod that got me into modding Homeworld 2. The Modular destroyers and the supercarrier especially had me more excited for new gameplay than anything else. Its a shame as of me writing this that REARM is discontinued for the time being, I can only hope future updates will come.