I have seen many musepoint guns that work like the HL2 combine turret that you get to use, and i would like to know how people build those.
You need the Wire extra addons whatever it is which includes the facer.
Just take an advanced pod controller and adv. Wire the x, y, z to the corresponding values on the facer. Then Wire the active of the pod controller to the on of the facer. Then just stick some turret on there and wire it up and there you go.
You could use Teta Bonitas mounted turret stool. Doesn’t require anything: http://www.garrysmod.org/downloads/?a=view&id=41175