NL:
Super Mario RPG: Legend of the Seven Stars is technically a single-player game, but was often jury-rigged into a multiplayer experience whenever I showed it to a friend.
We'd huddle around the SNES, each claiming a character in the party and passing the controller back and forth so we could enter a single attack or item use when it was their turn. Ownership of the third character would often be negotiated and alternated on a round-by-round basis. This was often Geno, because his coolness was way too prolific to fall under the hands of just one player.
NL:
It's a reflection of the technological times that it was 1989 before Nintendo produced a profitable portable - its grey and green screen was far from cutting edge, but its relative affordability and battery life that obliterated the competition helped the system become dominant in the market.