Array on a group of objects? (folders in Outliner?)

Is there a way to use an array on a group of objects or on a main object including it’s parented objects?
It would be quite helpful to put several objects in a folder in the Outliner and use an array on the folder.

Having objects in a folder would also be handy to easy turn on/off and to select all objects.
It would also be nice to have objects organized in folders, kind of like when you put different layers in organized folders in Photoshop.

Thanks

generaly groups are for that on/off but yep group in array would be nice however you can do this trick.

Select objects make them a group move to another layer. go back to layer where they where. Put there space group instance. select that group and thenn add modificator array.