This was something I found on the web a few months ago, before you may get too excited - keep in mind that the price is about $4000 I think.
http://www.procedural.com/
It's a procedural "city builder" - and would appear to work well with all sorts of multimedia. This program does look very cool, especially in its flexibility and the very easy way in which buildings and roads can be manipulated. While it'll be out of reach for most indie people (well here anyway), thought I might point it out.
GDT DEBATES - GO AND CONTRIBUTE

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