Sci-Fi FPS Reccomendations?

I've hardly played (the highly overrated :) Halo series and I don't know of any other game like Shattered Horizon (low gravity shooter) but Natural Selection is a great game.

X reunion + Xtended mod, not sure if the mod is compatible with Terran Conflict.

planetside 2 is ok

Star Wars: Republic Commando

Take a look at tribe ascend
It looks like halo ;)

interstellar marines ( early access, you can get all future updates and expansions if you buy the pre-alpha )

Natural Selection 2 is the tits

System Shock 2

The best ones have already been mentioned, but if you're looking for something that's more team-oriented, try Global Agenda. You can get many hours of entertainment out of it with the F2P, and if you get serious and want to play competitively, the fees/sub isn't that expensive. I did it for a while, but I just didn't have the time to keep it up.

http://www.bundlestars.com/all-bundles/fps-warriors-bundle/
check this bundle out it might suit your needs

Tribes: Ascend

Space FPS? I wouldn't call any of these a "Space FPS" including your examples. I think you mean a "Sci-Fi FPS", for which I would actually recommend the "TPS" Dead Space series. Despite the camera angle change, gameplay is fairly similar anyway.

If you want an actual "space FPS", Descent is always a highly recommended classic.

hmm maybe StarCitizen still not sure,but Kickstarter backers will receive a handgun when the game releases(or in some of the modules) so I guess there will be some first person combat,I mean they said that they were giving these hand guns so you can defend your ship so imo there will be combat other than just flying a ship,maybe when you are fighting in space and your ship gets raided like in Star Wars movies or Battlefront 2 where they just enter from the Hatch and you shoot each other till somebody survives...so I guess Star Citizen can pass on FPS :D

Doom 3 BFG

Prey is a good one but it's hard to find unfortunately.

About half of the FPS games? ;D

Freelancer.

UT 2004 or UT3.

well dont know why anyone named the Star wars Jedy knight saga...beautiful FPS ,maybe the best star wars games ever made...i don't played dark forces yet, it's very old, but Jedy outcast and jedy knight Jedy accademy are wonderful games... trust me and hurrt , buy them asap http://en.wikipedia.org/wiki/Star_Wars:_Jedi_Knight_%28series%29

Warframe

Unreal, Quake, Star wars

This?

http://store.steampowered.com/sub/2103/ here, you have maybe the best fps sci fi series on sale now...

Does Hard Reset count? Sci-fi, don't know if I'd call it space though.

And how is everyone 'forgetting' Aliens: Colonial Marines? xD

Unreal