BrewLAN is a mod for Supreme Commander: Forged Alliance that has been in on and off development by a team of one for almost a decade. It adds a wide variety of new units for all factions, as well as offering several new game modes and features. The core design goals for the mod are simple; to add new, interesting, and visually aesthetic units which complement those already in existence and to maximise technical compatibility with other mods.
One of my current projects is allowing the Gantry to build experimental units from other mods properly. The script that allows this can only do it on a unit by unit basis at the moment, and also disables the unit from being built by anything else, but here is one of the first things I tested; the Doomsday from the Total Mayhem mod. Which takes the Gantry just under 10 minutes at 764 mass per second to build.