Inspired by my thread on designing 4e specific generic terrains/structure maps...

Create a map that fits the "$100 million dollar action movie scene" instead of realism kind of terrain that is especially useful for 4e exciting battlemaps. This means large open areas, things for monsters to hide behind, hazards like pits, cliffs, quicksand, molten rivers of lava, difficult terrain, etc.

Theme should be anything you want, as long as it fits in the design paradigm described. An over-the-top battlemap made for heroic fights with bad guys and lots of minions. No 5 foot wide corridors or tiny rooms - everything is big. Try to make this a flashy environment.

Its an experiment I've been working on myself - and me, a guy who also develops campaign/modules for Pathfinder, what am I doing making maps specifically for D&D 4e??