5 out of 5 rating for Maze of the Blue Medusa
A glorious merging of old school sensibilities with a completely new and original style, organized incredibly well. NPCs are all given simple one-line "wants" and "does not want", making them very runnable on the fly. The content is definitely "weird" and surreal, and might not be what vanilla D&Ders want, but I absolutely loved both reading and running it. I adapted it to 5e on the fly (albeit a modded home version), and found that really easy to do. Players all started as 6th level wizards, so they had a lot of unusual resources at hand. It would no doubt be a completely different experience with a martial party, which I'd like to try sometime.
The PDF is also really well put together, with handy internal links galore.
Very highly recommended.