Just spotted the release of Doxylamine Moon: Overdose over at Doomworld and did a quick playthrough. Considering that well-designed and filled with lots of stuff to discover (it's actually a huge city where you can easily get lost), I considered it worth enough to be posted here as well ;) The author says that it's actually based on the Sacrament wad and story (though I actually can't tell as I have never heard of it before) and it's some kind of End of the World scenario that you're gonna encounter. You can find some screenshots and a download link in the actual release thread.