Idea for graphics software or plugin

I'm sometimes impressed when I see a building or institution that takes the trouble to orient plans and maps in different ways for their different situations. That is - when you look at a map or plan, the building rooms, roads or whatever you're trying to read are laid out in the same orientation as the physical location. If the room I'm looking for is the next on the right, the plan will show it to the right of the "you are here", but the plan around the corner which is placed on the opposite will will show the room, which is now to my left, on the left hand side of the plan. Most signs, however, are disappointingly oriented towards north, and when placed on a south-facing wall, require the reader to translate everything 180 degrees in order to make sense of it.

Which leads me to the idea that a graphics package should include tools that allow for the rotation of maps and plans by an arbitrary number of degrees from north to match the orientation of the surface where they will be posted, but leave all the text labels right-side up. This functionality is no doubt available in expensive CAD packages, but I'd like to see tools to do it in, say Powerpoint, or Illustrator, or whatever it is that most site-managers use to make up evacuation signs, plans, maps and other ad-hoc signage.