Figured this might be an interesting idea for a thread, post games that despite being awesome never really hit it big for whatever reason. People often call these cult classics or hidden gems or what not. Post from any era, any platform or PC.
I could post like 20 but to not suck all the air out of the room I'll limit it to two.
First is Kickle Cubicle, an a puzzle/action game for the NES released in 1988.
Puzzle games were always sort of a niche really, but this is not only an very interesting and often challenging puzzle game, but also has a lot of cool action elements, with a wide variety of enemies and bosses to fight. Out of the hundreds of people I met who ever owned an NES, exactly one of them had this game, thankfully they were a friend of my in the neighborhood which is how I knew about it and why I got it.
If you still like playing old school NES games and you've never played this, either buy it or download it.
The second is also a genre-bending game. You could qualify it as an action/puzzle/racing game (as much sense as that makes), Blast Corps by Rare, released in 1997 for the N64.
The gameplay is extremely unique and difficult to describe. Essentially a runaway nuclear carrier is careening out of control and if it hits anything it blows up, so your job is to clear stuff out of it's path. There's tremendous variety in the levels, vehicles, and techniques you use to do this. Probably due to it's extremely unique nature and also being overshadowed by Rare's other N64 titles, it's usually one of the best N64 titles that people have never played.