This guy has to be the most dedicated fan of Orbiter Space Flight Simulator. This is a 17-page forum thread fully loaded with screenshots and concept arts that this guys has put together for Orbiter. This guy even went as far as implementing a VC for the EVA suits. The ships are enormous [almost monumental] in size.

Aresa World Addon

There is also a video available.

Aresa World Video

I haven't been able to come up with any link to the addon so far. In fact, I'm not even sure if the addon is even complete.