one of the last D6 settings that was done by West End Games (and Bill Coffin worked on it). The setting involves a Dyson Sphere, an intergalactic empire in the process of fading from power, and lots of very interesting bits of technology that would be absolutely fascinating to explore from the point of view of the Fading Suns setting.
In this setting, of course, we're looking at Septimus just after its prime. But it's a Dyson Sphere (which in-game is called a Worldsphere), a classic bit of supertechnology consistent with the rumored wonders of Fading Suns' Second Republic!
The sheer size of the setting (with loads of trash and a few potentially dangerous treasures hiding in the ruins) is enough for an entire archeology-based campaign by itself. Of course you could go the Stargate Universe route and have the PCs suddenly cut off from the Known Worlds due to a Jumpgate malfunction and have them try to find a way to open a route back somehow.
Add to that nanomods, genomods, starships, weapons, armor, and psionic abilities (which in-game are called Metaphysics) and you have almost everything you could want as a portion of the huge, sprawling, Second Republic just before the fall.
And it's free to download.