For this voting I will go with Call of Duty. I played SWAT 3 a long time ago and I think it was also a 1st person shooting game, that is also fine. Its latest version SWAT 4 is also released and I am going to take a look at it.

swat is a good tactical game, which is not FPS, just like full spectrum warrior, where you play the commander..leading the team.

Doom I, the Ultimate Doom and the Final Doom have to be the best FPSs ever made.

After that its Half-Life 1.

CS:S is a good game, but its not great. There is no real single player side, and there is no story plot.

Its not like Doom, Half-Life, or Left 4 Dead where there is a story behind the game. Having a story plot helps pull the player into the game and creates an alternate universe.

I'd say Half Life 2, hands down.

Look at it today, it's still amongst the best graphics and IMO the best storyline.

Pretty sure alot of people love TF2 on PC, it's a fantastic game also.

Bioshock, no more words...

This is probably the right answer. I haven't got tired of playing this game. AVP was pretty good back in the day.