If you find Elite: Dangerous a too-contemporary spin on the space-trading theme, try Oolite, inspired directly by the original 8-bit masterpiece.
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You can be a millionaire trader, a combat fighter, a feared pirate, a lonely miner and much more just like the original game. What's more Oolite features over 2000 space systems, space stations and plenty of goods of which to trade and upgrade your ship. Another cool addition to the game, is customization: almost all parts of the game can be modified using simple free text and graphics tools and the developer states that over five hundred expansion packs are available, ranging from minor tweeks to new ships and giant missions.