Fredrick Pohl's Gateway (Score 2, Informative)

This game had a killer ability to suspend disbelief, and the story just sucked you right in. I worked as a telephone operator on graveyard shift at the time, and I would actually haul my 386 system into work so I could play the game during down times, then haul it all back home and play some more. Like a dork, I still find myself thinking about the game from time to time.