I just finished building/compiling a huge collection of Sci-Fi stuff. I'm selling the full version, unfortunately, but I figured I could post a few samples for free :) A few parts are included from previous projects, but I'd say 90% of this is original geometry.
1.) None of these parts are UV unwrapped
2.) Most of this is pretty high-poly, so not directly usable in a game (of course, you can create normal maps from it).
If anyone's interested, the full version of this file can be found here.
You can also vote on my future BlendSwap projects here.