Starflight II: Trade Routes of the Cloud Nebula is a space exploration game made by Electronic Arts in cooperation with Binary Systems in 1989. It was initially written for DOS on Intel 8086 and later PCs, but there were versions for M68k Macs and Amigas as well, released in 1991.
It was the official sequel to Starflight, and a worthy successor it was! Featuring shiny 16-color EGA and VGA graphics, while still being functional on CGA systems, it looked better than the original. It also included complex mechanisms for space combat, mining, and lifeform harvesting. There was a complex in-universe economy, and you could haggle with most aliens about prices of trade goods. It also had a deep, interesting storyline involving time travel and ancient conspiracies.
For me, this was the game that really sold me on the idea of video games. Sure, Asteroids was fun, and so was Space Invaders - but it was Starflight II that convinced me that video games could be more than a brief diversion. My only mistake was playing it before the original Starflight. Thanks to its in-depth economy, enjoyable combat system and large, diverse region of space to explore, it kept me entertained for months.
It wasn't without warts, however, most of them technical. The game itself had three options for installation. It came on two 5.25" floppy disks with instructions on how to create a 3.5" installation floppy. From there, it could be installed on four 360k 5.25" floppies, two 720k 3.5" floppies, one 1.2MB 5.25" or 1.44MB 3.5" floppy, or on a hard disk. I initially played it from 5.25" 360k disks, which was a very annoying experience. Doubly so because if you failed to exit the game correctly, your save would be destroyed, and you'd not only have to start over, but completely reinstall the game! An installation to hard disk had the same problem, but because hard disk access is so much faster than floppy, and you could make save backups, this was much less of a problem.
Also, the DOS version is very sensitive to the speed of the computer it's being played on. It works acceptably on an 8086 and is downright zippy on a 12MHz 80286. On a 25MHz 80386 it verges on too fast, while a 66MHz 80486DX2 was unplayably fast. If you're playing it on a 486 or later, you'll probably want to either use a program like MoSlo, or you'll want to emulate, either DOS or an entire PC. If you're just emulating DOS, you may well still need MoSlo, or you may need to severely overload the underlying Windows or Unix system. From experience, running Qemu under Solaris on a Sun Blade 2000, with FreeDOS as the host OS, provided acceptable though occasionally too fast performance. The Macintosh and Amiga versions automatically compensate for system speed. If you're looking to acquire this game today, I strongly recommend looking for the Mac version and running it under BasiliskII, or directly on a Mac if you have a 68k or PowerPC Mac, or the Amiga version and running it under e-UAE or WinUAE (or obviously, a real Amiga).
There was also an odd form of copy protection. Any time you left Starport, the game would force you to "calibrate your navigation system" by entering the number of stars of a certain color from a specified sector of space. You got this information by using the paper starmap that came with the game, and the little cardboard map device. If you got this wrong, nothing would happen at first, but later you'd be apprehended by the Interstel Corporate Police for piracy. You could fight them, but even if you won against the first wave, they just kept coming until you were destroyed. If you didn't fight, you were arrested (in-game, of course). Either way, game over. I fell victim to this a few times just because I honestly dinked up the 'calibration' process. I seem to remember that it was possible to save yourself if you did this by landing again, then launching, forcing a re-calibration. If you're playing the game now, make sure to get one of the various copy-protection cheatsheets unless you're lucky enough to still have the paper map. By now, though, that's unlikely - the game is 19 years old, and it's likely that even a legitimate copy will have had its map and decoder lost or destroyed.