The movie Gravity but with space guns.

This game is awesome, I like the idea that your in space shooting down other astronauts but the sad thing is that the multiplayer is dead & the single player option is just practicing on a server with bots (The community is trying to resurrect this game)

The layer of complexity added by the full six degrees of freedom makes it one of the most interesting FPS. The maps architecture complexity is increased accordingly which allows realizing the full potential of the movment mechanics. Thus, many attacking strategies are viable options, ranging from a simple straight line frontal rush, to silently squeezing through space and sneaking behind the opponent, including every possible direction in between. Navigating around the floating debris and obstacles in space is a unique feeling that this game provides masterfully.

Although not many people play it online anymore, there still is a small core of regular players, enough to have a lot of fun. UPDATE: This is unfortunately not true anymore. The game is no longer played online on a regular basis.

My favorite zero-gravity shooter. I mean, you can spin 360° around and your aiming and position is always relative to you where you are and where you are facing. You can shoot someone who is horizontal to you, or even spinning at the time with his thrusters. It's awesome. And graphically it's really really good looking. The only downside is that there are few people playing. But this easily beats other shooters in terms of gameplay and originality.

I took a risk with Shattered Horizon. It's an online-only FPS with motion-sickness-inducing six-degrees of freedom action. I find neither quality particularly endearing. Nonetheless, its high-frontier setting coupled with its low price were enough to convince me to part with my hard-earned money.

Considering it was developed by Futuremark, creators of those spiffy benchmark programs, the graphics were hardly as mind-blowing as I expected. Nonetheless, they were more than passable. It took me a while to get a hang of the slow, topsy-turvy maneuvering, but I rather enjoyed the mix of slow movement, inaccurate weapons and sudden death. The game offers a unique feature of "going dark", turning off your suit electronics which prevents you from showing up on other people's radar. Unfortunately, given the extremely low population of the game-servers (I met one other person still playing!) this makes combat extremely dull; it's impossible to find anybody! We spent one round of combat just flitting about the level trying to unsuccessfully locate one another.

The game does feature offline combat against 'bots but they are a poor replacement for the chaotic frenzy of human gamers. And the menu interface could have used an extra shine of polish, as it was rather bare bones. Its a shame this title never took off because, while it would hardly replace single-player gaming for me, its stately combat was more appealing to me than most other online FPS.