I put together a horror adventure for the Demon City backers and I'm making it available to y'all if you want it.
It's a "clue sandbox", meaning that there's some trouble and clues and people to ask about the trouble in every direction. There are dozens of NPCs fleshed out, along with their daily movements around the city and their (every-shifting) connection to The Horror. The idea being: the PCs can start anywhere and find their way (by hundreds of possible routes) into solving the murder--or becoming the next victim.
It's for Demon City, of course, but it's not a mechanics-heavy adventure so would be pretty easy to run in any horror system.
So far I haven't had any complaints from the backers, so...if you want one, email me: zakzsmith AT hawtmayle dawt calm. 20 Bucks.