probably the most interesting mod that I have seen. It allows AI moving in dog servers. Now the tanks and ships are moving and fighting, even if no humans are in there. Planes have waypoints, and they are working in comms between humans and AI and control towers.
http://allaircraftarcade.com/forum/viewtopic.php?t=15213&postdays=0&postorder=asc&start=0
At least the HL server Norwegian_FB is using it already.