Salvation Prophecy which is a cross between Freelancer, Space Rangers, and planetary battles ala Star Wars Battlefront. It was basically put together by one guy and for an indie, it is amazing. Drm free on Gamersgate and I discovered it over at Desura by accident while checking up on the progress on Project Zomboid.

Each element taken on it's own is kind of simple but put together it is quite addictive. This preview offers a interesting perspective.
http://www.thetechlabs.com/tech-news…tion-prophecy/