Sega Master System / Mark III / Game Gear
After enjoying vast success on various computers, this vast RPG was converted to the Sega Master System - and very successfully too! The storyline involves you being dragged into the inter-dimensional realm of Britannia to help Lord British and his chivalrous mates defeat the evil at work throughout the land.
You have to lead the four characters in your party around castle dungeons and through towns, woods and marshes, enlisting the help of friendly citizens along the way, and putting bandits and monsters to the sword. Dead guys leave behind treasure which lets you buy new gear in the local armourer's and pay for food, grog and information in the taverns.
Though this scores quite low on the graphics-ometer (apart from the occasional scene-setting pic), it has weeks, nay, months of gameplay packed into its chips, and a battery- backed save too! If role-playing is your idea of heaven, get hold of Ultima IV fast!