Nice thread, gonna have to look into some of these games.
One game I always like to mention is The Void (aka Tension aka Turgor) by Ice Pick Lodge (Pathologic).
It's a first person adventure, resource management, action weirdness where you seduce naked women, grow and harvest Color in an ecosystem consisting of the environment and your own body, draw glyphs in the style of Arx Fatalis for interaction or battle giant, grotesque monsters to survive another day in the afterlife, with hopes of being reincarnated.
You are a soul, stuck in the Void, a sort of purgatory inhabited by the beautiful, entrapped Sisters who long for Color and the disfigured, monstrous Brothers who roam the Void, jealously keeping the Sisters for themselves. The Void is a wild and incredible place, full of desolate, abstract locales, impossible places and monolithic structures. It also has its own ecosystem which is crucial to your survival.
All throughout the Void are little colored "plants" that hold Lympha, a raw form of Color. However, to make this resource usable for interaction, combat, health, stats etc. you need to process it. You do this by harvesting Lympha within "Hearts" inside your "body". These Hearts slowly process Lympha into a usable Color which you then spend by drawing glyphs on screen for a wide variety of uses. Suffice to say, you need to explore the Void, constantly harvesting Color all the while fighting surreal creatures, seducing Sisters and avoiding the wrath of the Brothers.
The general progress of the game follows your struggle to keep your Color containers filled, give Color to the Sisters to satisfy their hunger thus opening new areas and things to do and fight the Brothers in boss battles to survive. The gameplay outcomes can be varied and things can be solved in different ways. You can seduce a Sister and give her lots of Color but this will enrage a Brother responsible for her and you might get into more trouble than you bargained for.
The Void is probably the most unique game I have ever played. But with a lot of games like this, I've usually felt disappointed with some aspects like gameplay, story etc. This is not the case with The Void, for the most part. It is rough around the edges but it offers a satisfying, surreal and unique adventure I think everyone should experience.