Here is a map I created for my weekly GURPS fantasy game on OpenRPG. For the past year (in both real time and game time) my intrepid adventurers have been investigating a mysterious ode written on an even more mysterious scroll, which has led them to the abandoned, ruined, and haunted "holy isle" of the ancient source of all culture. (I posted an earlier "isometric" sketch of the isle here: http://www.cartographersguild.com/showthread.php?t=717)
In pressing onwards they came into a great hall which, after descending the stairs to the south of the room, opened to a vast, vaulted ceiling supported by great columns. The room is "lit" by the eerie glow of a waterfall at the far north side, which shines green. A great pool stands in the center of the room, filled by two "serpent" head statues that each vomit water; a tremendous statue of a man/serpent stands in the midst of this. Below each serpent is an arched tunnel; water falls in thin sheets inside, wetting anyone passing through. Because of the moisture, the entire room is covered in fungus and mold--putrid and disgusting and thick in the nostrils.
Beyond the spitting serpents are tunnels on the east and west, each ascending slightly to deposit the traveler behind/beneath the waterfall on a ledge, which eventually leads to the exit tunnel in the north.
Anyway, I'm posting the visual I created for this room along with the map. Both, as you can tell, I tried to give a gloomy, dark feel to fit the moment. All was done by hand in Photoshop (except the floor pattern on the map, which I borrowed from one fo the fine folks at the Dundjinni boards). Enjoy!