I probably haven't played near as many FPS games as other people on the boards so take this as you will!
1. Goldeneye- This was my first FPS game. I've never had as much fun with any FPS as I have with this one. Oddjob FTW! 
2.System Shock 2- This was the first game to scare me pretty bad. Plus, it was just insane. SHODAN ftw.
3. F.E.A.R- I loved the effects and creepy plot. Grenades were fun. :)
4. Perfect Dark- I played countless hours with my friends. Most of that fun came from weilding the Far-Sight XR-20.
5. Half-Life 2- I loved the plot. At the time I was enthralled by the graphics and physics. Oh, and Alyx Vance.
6. Bioshock- Unique environments, awesome atmosphere, plasmids, and plot.
7. Halo: Combat Evolved- Multiplayer with friends. Pistol.
8. Call Of Duty series-Loved the single player campaign. This game had a layer of polish that others lacked.
9. Quake series- Multiplayer with my buddies in the 2/3 and the single player in 4. The Strogg conversion was wicked.
10. Battlefield 1942- Absolutely loved the addicting multiplayer. Battlefield 2 was pretty close as well. Loved the tanks and sniping noobs.
Edit: What the hecK? how did I become king of the thread?
Person 1: Does Valkyria Chronicles have trophies?
Person 2: No.
Person 1: Forget it. I'm not buying it.
Person 2: Wait! It's amazing! Unique, charming, drop dead gorgeous... Hello?
