I'm not an FPS kind of guy, but I really enjoyed Project Snowblind. The gameplay variety was superb. You'd lead a massive assault with huge numbers of soldiers on an enemy compound in one mission, then find yourself sneaking alone through a top-secret base in the next one. And let's not forget the augmentations: slow down time, put up a peronal shield, stun foes with an electric pulse, and send them flying with a super-strong punch.

And the weapons! My favorite weapon in Snowblind, and my nominee for The Most Useful Weapon Of All Time, is the Icepick. Witht his bad boy, you can hack into computer consoles and ake control of robots. So, if the next room has a heavily-armed robot mech in it, you don't have to use ammo destroying it. Just hide where it can't see you and shoot it with the Icepick. Presto! You're in control of the robot, and can cackle with glee as you mow down hapless soldiers. When they're gone, just walk the robot to the far side of the room, sever the connection, and exit the room.

Probably the Delta Force series, I've played them since the beginning but their games are fading away so, CoD from now on. I'll always be loyal to Doom as well.

Call of Duty 4 cause it's the only one I have. But I do love COD4!!! RTS!!!!!!!!!!

AVP 'nough said.

oh and Phalnax811 is not a real boy

half life 2 the complete vibe in that game is amazing for the rest halo1 and call of duty

Best pure FPS: Half Life 2 and it's subsequent episodes.

Best Tactical FPS: Rainbow Six Raven Shield and its expansions (the last real Tom Clancy game, sadly)

Best Multiplayer FPS: Team Fortress 2

UT99.

I actually like UT3's core gameplay more, but the rest of the game brings it down. :/

Red Orchestra would be a close second, or tied with even.

here is my top 5 for best fps not saying that they are the best but just the most fun i had/have with these games

1:battlefield vietnam

2:battlefield 1942 desert combat mod

3:call of duty 4 multiplayer

4:call od duty single player/multiplayer

5:wolfestein eneymy territory [remember the free online game?? omg so much fun i had with this game]

anyway thats my 2 cents

I have a question for you people who plays FPS religiously.  That is, how do you deal with motion sickness when playing FPS.  Oh my god, half an hour of half life 1 and i want to put my head into the toilet for puking. 

I tried playing serious sam 2, and i am telling you..the feeling of nasuea was not fun.

Most games aren't enough to inuce motion sickness in me, but if any do, they get promptly sold/tossed, and are forgotten.