What is your favorite weapon amongst all FPS games?

BFG? Farsight? Katana? name thy tool of slaying and what FPS in which we may find it.

Any rifle or sub-machine gun from Killzone 2. They feel so heavy when firing them. Also, the sound work on the weapons, in particular the assault rifles are great!

The nano disintegrater gun from red faction: guerilla.
Edit: My bad, i forgot it was FPS.. I'd say grav gun then.

I'm a big fan of the Redeemer from Unreal Tournament 3. The redeemer was in the other games but the way it unfolds and looks so threatening in Unreal Tournament 3 is just great.

Pretty much any (preferably Heavy) Sniper rifle. The 99C-S2 AM from Halo, Rail Driver from RF:G or the Intervention/M82 from MW2 if you wanna get specific.
 
Secondly would be any G36 variant (LMG, AR, etc) or the PPSh-41. Also the Nano Rifle from RF:G.
 
If you just wanna generalize, Snipers then Machine guns (followed by ARs with under barrel grenade launcher when applicable) would be my favorites.
 
Though the "Game Ender" weapons are great too (Redeemer, Fat Man MIRV).

The monkey gun in Timesplitters 3  or the tesla cannon in Fallout 3. 

SHOTGUN. its good in any game that requires shooting something in close range

any hangun or shotgun from and FPS any where.  CQC is my middle name.

Gravity Gun, What else?

" Gravity Gun, What else? "

The Pulse Rifle from half-Life 2.

a good winchester-type rifle, god am i excited for red dead redemption. 
 
double pistols are always great too.

Shotgun. No matter what form it takes, always the shotgun.

Portal gun.

i don't what the games name is.. but very bloody and highly disturbing. BUT! you could shoot kittys out of an shotgun and an m16, so that was awesome. 
 
edit; i think it was postal 2 or something

" i don't what the games name is.. but very bloody and highly disturbing. BUT! you could shoot kittys out of an shotgun and an m16, so that was awesome "

Probably the Combine Pulse Rifle, Half Life 2. The noise that that thing makes is orgasmic, it sounds so powerful. Plus, have you seen how that thing reloads? So cool.

" @dylanderoo said:

" i don't what the games name is.. but very bloody and highly disturbing. BUT! you could shoot kittys out of an shotgun and an m16, so that was awesome "

T'was a gun(s?) from Postal If'n I remember. Although the pee action was highly entertaining too. "

I'm with the shotgunners here. In almost any form, shotty is king. And my secondary will be dual handguns, or a single handcannon. 
 
But when I try to think of standout weapons in FPSs I've played, the only thing that comes to mind is ...  

The Shrink Cannon from Duke Nukem 3D and the shotgun from the original Half-Life, still my favorite shotgun.

BFG-9000. The original room clearer, and the only true answer.  
 
 
But in all seriousness, in general, I love me a good shotgun. Halo's shotgun was pretty decent, don't like COD's or GOW's shotguns though. Borderlands had some awesome ones, and Counter Strike as well.

The gun in Painkiller that shoots wooden steaks and pins enemies to walls. That gun was fucking awesome.

" GRAVITY GUN!! Seriously that gun is sick.   "

All time favorite: Shotgun.

Carbine from Halo 3. Better than the Battle Rifle if you use it right.

the Chain Gun from Red Faction 2 that had an x-ray scope and could shoot through walls. Ungodly things could be done and you felt like the best bastard in the world. Also, the Antipersonnel Gun in Team Deathmatch with team kills off. You could coat someone in it, send them in as a suicide bomb and when the little explosives go off, you laugh because they didn't die

The "Shrink Ray" In Duke Nukem 3D. Nothing like reducing a creature to the size of your foot and then stomping on him!

The BR from Halo 3.  That baby is devastating in the right hands.

I guess I would have to say the STG. 44 from World at War, which is also the MP44 in previous Call of Duty games. And yes, that is how I got my username both on this site and on many other sites. But at the same time, I love guns with really high fire rates in my games, as well as old weapons. For example, I really like the F2000 in Modern Warfare 2 just for the fire rate and the looks. I also like using it in Bad Company 2 for much the same reason - it looks cool and it fires quickly. So I guess this is how my preference works: 
 

1. 'Classic' weaponry (World War II era) 
   
2. Weapons with high rates of fire 
   
3. Weapons that sound or look cool
   

The crossbow from Half-Life 1 & 2.

The shotty. I'm more of a "run up and blast the guy's nuts off" kind of guy in FPS's

That gun from F.E.A.R. that shoots needles, or something like that. Nothing better than pinning an enemy to the wall by his head.

Quake 3 Arena's (or QuakeLIVE) Rocket Launcher is my favorite gun of all time followed closely by the Deagle from Counter-Strike.

The FN-FAL from Wasteland HL, a mod I guarantee nobody here has played.

Altered grav gun from HL2 
Katana from L4D2

M82A1A sniper rifle from the SOCOM games.

Glock.
BOPBOPBOPBOP

Doom 2 double barrel shotgun

...and the Flak Cannon

Davy Crockett or Fat Man

Shotgun in Fear 1

The guns in Far Cry 2 are all so great!They sound and look phenomenal. 
Also,RF:G's armaments,and UT3 had some great Sci-Fi weapons.

Cerebral Bore of Turok 2. Guess what it does...