Thanks to all of you, now I'm looking for some time to play the game and discover crossfire.
And I've just seen that there's also an X3 section, that I'll surely visit sooner or later.
I must amit that tough I've discovered '"space simulation games" by freelancer, the games that kept me busy for almost 5 years by now are x3 and it's "addons". Just a shame that there is no multiplayer feature for these games.