I suppose my ideal would be something inspired by Outpost or such, or even Hitler's bizarre plans for Nazi Germany. (Yes, yes, I know, that's kind of creepy of me, but that guy's sense of architecture was fantastic. In the sense that it had no place in reality but was well-suited to fantasy. :P ) Either something grandiose, or something futuristic like enclosed buildings with elevated walkways, or something simply interesting.
Anybody know of any really decent tilesets to look at and play with?

I would have to look for a fansite, the same as you.