Metal Gear Solid: The Twin Snakes: Special Disc

Metal Gear Special Disc is a bonus disc included with the Premium Package edition of Metal Gear Solid: The Twin Snakes exclusive to Japan. It's essentially the Famicom Metal Gear running on an emulator with a trailer for Twin Snakes itself as a bonus.

Hilariously, it contains a warning to players regarding Hideo Kojima's lack of involvement with the Famicom version before booting the game.