Heroes of Monkey Tavern is a short pure dungeon crawl with a strong Dungeon Master nostalgic feel. There is no real story past the intro, you just wander through the dungeon exploring, killing, looting and solving the occasional puzzle. It’s short, under 8 hours total to complete.
Vaporum is a steampunk version of Legend of Grimrock. It has puzzles, lots of combat, good graphics/music/UI and an odd little “bullet time” mechanic that was tacked on after the fact (but works very well) to allow the player to slow the real-time combat during encounters. Apparently it was too fast and thus too difficult in the original release.