It seems that every
Nintendo console winds up with a defacto
mascot; a character that is most commonly identified with the system. The
Nintendo Entertainment System had
Mario, the
Game Boy had
Pikachu, and the
Famicom Disk System had... Diskun! Yeah, I've never heard of him either. Nevertheless he was the Japanese
Famicom Disk System's mascot, although he never appeared in a game of his own. He was primarily featured on the system's packaging and promotional literature. If you saw Diskun then you knew you were only moments away from disk-related fun!
Diskun himself is basically a yellow square, thus associating him with the yellow disks that the Famicom Disk System used. He has little feet, rounded hands, and two large eyes that. It should be noted that Diskun is cross-eyed. His square-shaped body has a small notch removed from the bottom (right where the crotch would be - poor guy) to further link his image with that of a disk.
So what happened to Diskun? After the Famicom Disk System was pulled from the shelves and the disk writer units were removed from stores he fell to the wayside along with the other forgotten Nintendo characters, such as the Robotic Operating Buddy, Tamagon, and Stanley the Bugman. The little yellow fellow did make a cameo appearance in Super Smash Bros. Melee for the Nintendo GameCube. Diskun appears as a trophy in the game and, to back up his elusive nature, his trophy is one of the most difficult to acquire in the whole game. The Diskun trohpy is awarded if all 249 different bonus scores are earned during gameplay.
References:
http://www.classicgaming.com/nindb/