Did you know that System Shock, the highly influential PC game of the early 90s that went on to inspire even more famous titles like Deus Ex and BioShock, was pitched for the Sega Genesis at one time? Game journalist Joe Martin managed to get his hands on an internal pitch from the game's publisher, Origin Systems, that sought a Genesis port to be shipped in September 1994. (Notice that the game is referred to as "Citadel," likely its in-development name.)
Does this pitch remind you of anything? The format is not dissimilar to your typical Kickstarter campaign, right down to the risks and budget requirements (but minus stretch goals, obviously). This port would have only required a modest $200K, which would translate into just over $320K today when adjusted for inflation. Obviously, the pitch wasn't accepted, since Sega players never did get that landmark "first-person walking around" adventure.
This is an interesting peek into what could have been, from a time when console ports of PC games turned out much differently compared to the originals. System Shock on Genesis would have been its own beast for sure — too bad we'll never know.