I'd say most people, haven't heard of the following: Dungeon Explorer, R-type, and Keith Courage in alpha zones, All for the Turbografx16. Dungeon explorer is a supremely fun game, where you get to choose your charcter from fighter, to elf, from warlock to princess, and lots of other fun characters, then you go on whatever quest you king instructs you to, while collecting magic and temporary stat boosters to level up and power you character to the end. R-type was a space shooter game were you go on and defeat the evil bydo, with powerful "Force" and wave cannons. It was remade for a few other systems as R-type Final. Extremely fun if your into blasting other aliens to pieces with an indestructible power, while being a challenging game. Keith Courage, though, I have to say was not very enjoyable for me. You go from being a boy with a small sword in the grassy plains to some battle suit in a death zone of firey death. You can go buy stuff or have your fortune told and I'm not entirely sure what the point ever was but you can get some enjoyment out of it, if you can manage to beat the bosses.
Then we have the Game Gear, (found in PS4's bookshelf, ironically) where our favorite game was Defenders of oasis, especially when the cartridge started to die and we got games that had never existed saved over our files with the most peculiar of items. The point of this game was I thought to save the princess or something. I never really got too far in it, but you get a small team and fight enemies. Not the most difficult game in the world, considering if you reset the game during a fight, it will be like the fight never happened. XD
MY friends have never even heard of a Sega Genesis though, save for one who has a family member who works with games and knows all of the systems. So I could include all of the games.
Here's a random game we got one a demo disc once, TELETUBBIES XDDDDDDDDDDDDDD! It was absolutely pointless...nothing more than that.