Star Fighter 3000: A somewhat arcadey sci-fi flight sim with a checkered history. Originally released for the Acorn Archimedes, it saw a release for the Panasonic 3DO, and later the PS1 and Sega Saturn. You flew around in your aircraft, and everytime you destroyed something, you could pick up colorful shapes that when they were arranged in a certain order resulted in power ups for your aircraft. PS1 version (via Duckstation) is easiest to get into emulation wise followed by the 3DO version (via RetroArch). Also, apparently the original Acorn version also received updates YEARS after it's original release, but good luck getting it to work if you have no experience with RISC OS (I tried for days to get it to work, but it all flew over my head, as the command prompt syntax was completely foreign to me even with slight experience in both MS-DOS and Linux Mint).

Space Hulk: Vengeance of the Blood Angels: Sequel to the original Space Hulk game for DOS and Amiga, it was originally released for the Panasonic 3DO and ported to the PS1, Saturn, and PC. It combines elements of both First Person Shooters and Turn Based Strategy, which along with the asymmetrical nature of the gameplay (5 or so slow Terminators vs swarms of lighting fast Genestealers), makes for a type of game that I have not seen repeated since. To this day, I hold the position that Space Hulk: Ascension and Space Hulk: Deathwing are two halves of what should be one big game.

SimCopter and Streets of SimCity: Both are fun but flawed games with troubled development histories. Their gameplay styles differed somewhat, but you could create a city from scratch in SimCity 2000, save it, then use it in either game (from the air or from the ground, respectively). Some mad lad even went out of their way to create patches so that they could run on modern machines with little to no issue.