I have been working on a thing actually, and it's going pretty well. I'll probably end up making a topic for it later on, but right now I can tell you guys it's about a space mission to either Tau Ceti e or Alpha Centauri Bb (Although probably Alpha Centauri) and [Redacted] along the way so you have to [Redacted] and make tough choices n stuff.
I want it to take player decision making into account, and so making different decisions leads you down different story paths, and I'm thinking there's gonna be a crew reputation system, where you choose between good rep for your group of companions and bad for your crew, or vice versa. There will be some decisions that gain or loose rep for both though, so it's not either or, but I think trying to keep a balance of positive rep among the entirety of the ship could be a cool aspect of the game.
I'm currently building it on the CryEngine 3 game engine, so it'll definitely be able to handle realistic graphics and physics. I've even been changing the source code so that the physics actually work the way I want it. (I'm trying to make physics in the game as accurate to real life as possible, and this means a LOT of research. But it's fun.)
For modeling, I've been using AutoDesk and their tools (Holy crap MAYA is so intensive on my PC) and things have been going well over all. I may post concept art and such on the topic for you guys.