PlannedAssault lets you:
+ pick pre-configured squads and platoons from the ArmA / Arma II game and mods
+ place platoons and objectives on the map
+ define the situation and story
+ wait a bit for the mission to be generated...
+ download your mission, and finally
+ experience large scale combined arms maneuvers from both friendly and hostile troops

Behind the screens, PlannedAssaults takes care the Arma mission creation technicalities (waypoints, triggers, mission end conditions, synchronization, briefing, tasks, modules, team switching).
It also comes up with plans for all units, so there's no need for you to command friendly troops or tell enemy troops what to do.
When applicable, PlannedAssault will coordinate artillery, close air support, armor, AA and infantry into combined arms attack or defense.

If you like large scale battles involving your favorite units, and want to test your skills as tank gunner, a forward observer, a gunship pilot, register a free account at plannedassault.com and give it a go.