I created these two encounter maps for use in a one-shot D&D game I ran at a conference last week. The scenes were modeled and rendered in 3DSMax, and the grids were added in PhotoShop, along with some contrast, lightness, and saturation adjustments for better print output. The maps were printed full size from the Costco photo center (At under ten bucks a print for 20x30, with the prints available in an hour in-store, or delivered by mail, I can't recommend this enough), and went over great in play.
The scenes were built using a variety of assets I had sitting around. I used textures from my Detailed Terrain mod for Oblivion, and some assorted prop models I've made over the years, so they came together pretty quickly. The keep map in particular was produced in under an hour (plus render time), before I headed out to catch my plane to the conference where I ran the game. There's some tiling in the stone work I'm not thrilled with, and the lightning could be more dramatic, but I like the results on the whole.
Comments and criticism are welcome, as always.