For pure dungeon crawl, trap-riddled goodness I highly reccommend The Tomb of the Iron Medusa by Mike Shel, I have copy/pasted my review for you here:
There's an old adage that goes "what's old is new" and Tomb of the Iron Medusa fits that like a glove. I'll be honest: I'm an old-school gamer and a sucker for dungeon crawls, but having played them so many times for so many years has made me somewhat fickle. There are many dungeon crawls out there, both good and bad, but only a few that are truly great. Unless its great, I usually wont GM it. See what I mean? Fickle.
Mike Shel's Tomb of the Iron Medusa is a great dungeon crawl. It takes an old-fashioned setting (a trap-laden tomb) and makes it fresh,exciting, and fun again. It breathes a lot of new life into old ideas without relying on convoluted plots, mandatory events/encounters or tons of filler. Mike Shel is an excellent writer who keeps it simple. Unlike some writers that try to shoehorn too much story/adventure around the game mechanics, he lets game crunch work around his ideas and his writing style has a certain sophistication that is rarely seen, making the adventure both more believable and immersive.
The backstory, which involves a disgraced aristocratic family under a curse,is intriguing and sets the stage for the PCs to investigate the tomb. As the party progresses, they will have to deal with an assortment of challenging puzzles, traps, and monsters while unraveling important pieces of story that could affect an entire kingdom (which can easily be placed in any fantasy game world.) Some of the monster encounters are quite tough, but not overly so. Personally, I prefer a module where certain encounters are a little tougher, rather than easier, on a high level party. Also, while the tomb itself is self-contained, there are various ways to explore it so the PCs are not necessarily on a set linear path. Indeed, they may even encounter the "final boss" near the beginning - depending where they go. As the party continues, more of the story behind the fate of the cursed family is weaved into the adventure and the transitions between narrative and active playing are seamless. Some may balk at some of the story moments, but I thought they were really well done. More importantly, the story is kept interesting from start to finish and ultimately gives the players the freedom to decide their destiny, which is always a sign of good adventure design.
The module presentation is good, but not great. Compared to other adventures of the Pathfinder Module line its about the same, although the artwork has improved lately. I thought the illustrations really helped capture the mood and atmoshere of the adventure. The maps are nicely done too, clear and easy to read - nothing too complicated.
Whether run as a quick dungeon crawl or fitted into a much larger campaign, Tomb of the Iron Medusa is an excellent adventure. Its great to see Mike Shel back and I look forward to more from him in the future.
Its for high level play (14th level) and not a megadungeon, but could easily be inserted into a piecemeal dungeon crawl campaign. I also really enjoyed The Black Monastery, but I suspect its not what you're looking for as it is more of a sandbox, Disneyland-style dungeon where anything goes and does not have any real coherent eco-structure. That said, the random nature of the monastery does have a rhyme and reason to it (with an intriguing background story) and offers a lot of fun, unexpected encounters.
The Shattered Star AP is, like most of Paizo's AP lines, very good but about two books too long. I found books 3 and 4 to be the unecessary culprits in this series, but it starts off well with the first two modules and the final two books are amazing. YMMV.