Top down perspective maps can be interesting, but they are only good for smaller areas as the farther away from the center point the more the "central" walls will hide what is against them.

I had to learn how to do these types of drawings for one of the drafting classes I took in college, but that was all done by hand. I haven't tried on the computer, but the effect could be easily achieved by using something like Poser and using the auxiliary camera in a top down view so that you get the perspective. Now trying to draw it in something like PS would be an achievement for sure. I imagine that Illustrator would be able to handle this fairly well given its vector capabilities.

I will be very interested to see what you come up with and how you use it.