The weapon you couldn't do without

[AdjectiveAnimal]

The dart gun in Fallout 3. Deathclaws just weren't scary anymore after that point.

 

[the monopoly guy]

I normally gravitate towards psitols in games. Dunno why, maybe becasue it's sort of the underdog. Or not.

In TF2 it's knife or nothing.

EDIT: However, in some servers in HL2M the crossbow not only hold 40 bolts, but is semi-automatic making it just devastating.

 

[Eclectic Dreck]

Sniper rifle. Normally though, given a chance I'd load myself with as many weapons as possible. Using a modified holster I'd have a variety of different handguns of various types, including the trusty old Magnum and maybe some sort of plasma weapon (Halo) or the Torque Bow (Gears of War). Then attached to my back would be a strap that holds probably one other longer range weapon, possibly a RAWKIT LAWNCHAIR! Then I'd have lightweight swords in scabbards on another belt just below the holsters. That way I'd have long, mid and short range capabilities as well as a lower chance of running out of ammo.

Note that in real life I have actually trained with military issue weapons, although I am not a military person at all, merely a student with too much time on his hands. My friend does fencing so I could learn the basics of sword fighting from him, and I'm actually a decent shot with most guns I've used before. As for the rocket launcher, does that really need specialist training? Just point, fire and BOOM!!!

Probably be a bit hard to move with all that hardware on, and you almost certainly couldn't "fence" in the European style.

That said, I tend to adore shotguns in most games. Or flame throwers. Or whatever other staggeringly powerful short ranged weapons there are.

In quake though the answer is almost certainly the rocket launcher.

 

[geldonyetich]

The quicksave/quickload keys.

Really, it's the most powerful weapon they give you.

 

[Inverse Skies]

I'm going to have to say limit breaks from any of the more recent Final Fantasy's. Sometimes when everything was going wrong, you would be able to claw yourself back with one of these, especially one of the awesome ones like omnislash or lionheart, or even Yuna's one (an aeon in overdrive? hell yes!)

 

[Nigh Invulnerable]

Explosives like mines, grenades, etc. As soon as I see a set of proximity mines or some such boom device I start to get giddy and giggle like a maniac. My friends hate me for it because I tend to just drop mines randomly or chuck grenades into weird places. Or lightsabers. No game makes me feel happier than a Star Wars game when I earn a lightsaber.

 

[Snowalker]

The best weapon, eh? I guess.. Why is there no game with a scythe? Anyhow, I loved the crossbow from Half-Life 2

 

[ChromeAlchemist]

G3 till the bitter end.

Failing that the hunting rifle from L4D.

 

[CirrusEpix]

As a flash artist, ctl-z FTW.

 

[PirateKing]

The shotgun in the library level in Halo comes to mind.
Or the lightning plasmid in Bioshock. All purpose that one.

 

[Roamin11]

Dart gun in Fallout 3, the wepon of a assin of sorts

 

[Arcyde]

Any sniper rifle or shotgun in any game

 

[Nohra]

Always, always, always a sniper rifle. Eliminating a particularly difficult enemy position from long range /always/ makes life an incredible deal easier. Plugging Troika gunners in GoW1 and 2, taking out Men in Black from Deus Ex, and ending countless other lives in games from Fallout 1 to Mass Effect, one shot, one kill saves a lot of stress.

 

[gamegod25]

Shotgun. A shooter without one (of any kind) would be like a JRPG without skinny, underdressed girls pretending to be guys ^_^

 

[Dirty Apple]

It all depends on the game:

Counter-Strike:Source - SG 552
Left 4 Dead - Auto Shotgun
Fallout 3 - Scoped Magnum
Call of Duty 4 - Silenced MP5

 

[Frank_Sinatra_]

RYNO 4-Ever.

 

[Dufferking75]

HL2 Revolver and Halo 3 Energy Sword

 

[sir pugglez]

Voo Doo doll in blood.
or the krieg 552

 

[Japgat]

can't believe this hasn't been mentioned yet.
Plasma cutter from dead space.