I've still got a Sega Genesis plugged into my TV, but I have long since lost or sold most of my games for it. The only ones that I have held on to, and still play, are Sonic 1, Sonic 2, Sonic and Knuckles, Pacman, Dinosaurs for Hire, Boogerman, and Radical Rex. Some other great games that I owned, and have no idea what happened to them, include Pitfall and Primal Rage. Those two games were great, but I no longer own them and I do not remember selling them.
I've always been more of a Nintendo kid, to be honest, but the Sega Genesis was a great system with some good games.