So I've been playing ConstantCon games, firstly with Evan Elkins from In Places Deep and then when Evan had technical trouble Jeff Rients from Jeff's Gameblog did an emergency pick-up game.
Yes I felt the urge to run my own game. Of course I couldn't use DaD's RPG for it, nor the Great Campaign Setting. So I went through my notes for something I could recycle. First off I found some rare paper-based notes for Port Manteau, or as my notes refered to it Port Marion.
Port Manteau was a setting I constructed around the rambling chat-rp threads from the Fortean Times message board back in the day I moderated them. It was a town based off of the famous Port Merion and the general backstory was inspired by the plot of the classic TV series The Prisoner. The inhabitants had all been imprisoned there by the Powers That Be because they were all digging too deeply into the real nature of the world. Of course it wasn't just the people who investigated the world's mysteries that were winding up there, the mysteries themselves were winding up on the Island of Forteana. After all the best way to keep those who love to investigate mysteries from escaping is to give them mysteries to investigate. Thus the sewers were full of Reptoids battling the local Bog Pygmies (or Lizard Men v. Goblins) and numerous other cryptoids, cryptids and crypts dotted the island. The God of Gambles ran the local casino and Chinese restaurant "Master Chow's"; the local Tailor was Sidney Stratton and Rodney the BarThing, the elder god of bar stewards, worked the bar at JW's and simultaneously the Trolls Head pub across the road. The town was 'ruled' by the Moderators, the wardens of the prison who were themselves prisoners, only prisoners powerful enough to leave under their own power and so were kept contained by the duty to police the island. They ruled from the Fortress of Fort high above the town upon the slopes of the Black Mountains. The Interdimnesional Moorland was desolate, marked only by the exposed fossils of dragons and giant; the lonely henge and the mysterious crater known only as Buttock's Hole. There was the deadly and impassable fire swamp, filled with Rodents of Unusual Size. The Fnord Fjord with Bog End, where lives civilised Bog Pygmies (or Halflings). The Templar Wood, dark, mysterious, wild and filled with ruins. Lastly lake Clovis, deep and foreboding with at least one lake monster, possibly more.
While Port Manteau would make a lovely living sandbox setting I don't think I could do it justice. I also don't think it's OSR material unless, by OSR you mean Chill or the strange hybrid that the Chaosium system keeps wanting to collapse into. My notes suggest that my first choice was GURPS closely followed by an obscure system called Cosmic Syncronicity.
Then I found two little used locations for D&D. Firstly was Fort Flaime, a ruined fortress with a village within it's walls, no key and only the village was mapped. The players had rejected it as an adventure location, twice, and so I hadn't gone any further with it. Then there was the Ogre's Cairn. It was the first 3.x location I had created. It had its moments when I ran it through one time. The PC's had recruited it's signature monster, a Dragonne called "I" and I'd never felt like revisiting it.
It struck me that if I put Fort Flaime on top of the Ogre's Cairn and connected the two locations directly I could build a modest Megadungeon with very little work. Of course I need to create a nearby town, Flaimehaven, but that was the work of about an hour (still need to work mapping it and Vornheim is not helping me as it did for the mapping the city for the Celestial Door and the southern city in the Great Campaign. Meh).
I'm nuts, are't I.