One of a handful of games that spawned a whole new genre, Starflight is arguably THE best space adventure game ever made.
Despite the (initially) lackluster plot (gather a crew and equip a ship to explore the unknown galaxy-- in true Star Trek fashion), Starflight introduces numerous features that set new standards for subsequent space epics (such as the better known and better sold Star Control 2): real-time play, awe-inspiring hundreds of galaxies (each with several planets), and many alien races (each with its unique language and culture). Although the game has an overarching plot (involving a sinister scheme you must expose), the sheer number of things you can do and star systems you can explore makes it incredibly open-ended. You can barter with alien races, mine planets for artifacts, improve skills of your crew, survive frantic space combats, and marvel at fractal surfaces that make each planet seem unique (watching your craft land gently on a planet is one of the most memorable moments of my entire gaming career). The scope of the game, and the elegance with which it is conveyed, makes Starflight the closest computer games ever come to what an actual space exploration must feel like.
Every facet of the game, from the great gameplay, user interface, and graphics, is so polished that what little flaws there are (such as the fact that artifacts are a bit difficult to figure out) aren't even worth mentioning. Last but not least, the ending sequence is one of the most impressive and appropriate I've ever seen in a game. From the start to finish, Starflight is one very well designed, well polished, and incredibly addictive game you'll play over and over again just to appreciate the amount of man-hours and love Binary Systems had put into the game. Starflight is that rare game that truly stands the test of time, and still attracts a large following more than a decade after its initial release. If you want to play only ONE space adventure ever, this is it.
Note: True Spaceflight fans should check out its sequel, as well as Protostar -- the true Starflight 3 that wasn't allowed to use the name. The download below contains the game, as well as various fan-made utilities (such as VGA patch) that will greatly enhance your Starflight experience. The manual download contains both PDF manual and starmap. Enjoy :)