I'm going to be running a West Marches style campaign, assuming I can get players (see the ongoing southern reaches campaign on Bugbears for Breakfast for what I mean by this).
Anyway, I've been working on a random dungeon so that they have somewhere to go that's a bit closer than town, but still dangerous, although it's safe enough to sleep in for a few nights, assuming they keep it cleared
It's not complete yet, but here's the most distinguishing feature:
Room 1, Level 1: An octagonal room. There is nothing here other than the stairs to the surface. All walls are set with doors. The lower right door leads to...
Room ?, Level 1: An octagonal room. There is a flight of stairs in the center of the chamber. The smell of damp and decay wafts up from the darkness below.
Room 1, Level 2: You have entered an octagonal chamber. There is the skeletal corpse of another adventurer laying against the far wall, with some flesh still hanging from the bones. This is the source of the stench of rotting meat. (The corpse is a Skeleton, which will awaken if the bones are disturbed.)
Room 3, Level 2: There is the sound of loud breathing, as well as the smell of smoke and cooking meat coming from behind the door. If opened the party will see an ogre roasting the spitted body of a hobgoblin. The room is octagonal. The party will have a 50% chance to simply leave (subject to modifiers), in which case he will not notice thier retreat, and will finish cooking the hobgoblin.
Noticing a trend here? Those are the only octagonal rooms in the dungeon, and all of them have stairs to another level.