Those of wondering what all the fuss is about when it comes to a lot of us mentioning this title, here's a full walkthrough of the whole game, which shows just about everything there is to see, only without the atmosphere of the engrossing sound effects and the actual narrative.
You're probably thinking that you've seen a lot of stuff before, Doom 3 for instance, note that Doom 3 copied a lot of ideas from SS2 which is why the game got hyped to be more than it was ever going to turn out to be. Also note that this game is from 1999, so there's bound to be plenty of things copied from it in other future titles.
Spoilers aplenty ahead:
http://www.visualwalkthroughs.com/syste ... hrough.htm
Take note that there's a download for a piece of Shodan's dialogue there, back in the day hearing this for the first time scared the shit out of me ![]()
Enjoy.