best in-game item EVER.

[Omnidum]

The Chicken Drumstick from both MediEvil I & II. The enemies gets turned into roasted chickens in a blue flash! Epic fun.

 

[Beefjerky]

The BFG-9000 from Doom. That's pure love right there.

 

[GuerrillaClock]

Cerebral Bore.
Bzzzzzzzzzzzzzzzzspppisssssssshhhhhhhhhhhhhhh!
Boom.

 

[Ghost Wolf]

The Redeemer from Unreal Tournament.

The Speargun from the AvP series (probably the source of inspiration for the HL2 crossbow).

The Moonraker Laser from Goldeneye.

Any of the big guns from Rise of the Triad.

 

[Eipok Kruden]

There's a few things from Castle Crashers that are just too awesome to describe with words: The ham, the lobster, the lightsaber, and the bipolar polar bear.

 

[videot76]

The Ring of Gaxx from Baldurs Gate 2. ESPECIALLY when you managed to pickpocket it from Kangaxx, and then looted another one from his corpse afterwards...

 

[Rossmallo]

The Mag-Charger, in Multiplayer of Timesplitters 3.
Sniper Rifle, Thermal Scope and Railgun in one. It's actually possible to spawn camp people in Capture the Bag while standing in your own base with it.

 

[Surggical_Scar]

The Log-Launcher from Painkiller.

Oh, and that gun which fires Shurikens and Lightning.

Actually, just Painkiller in general - that was truly awesome.

 

[Space Spoons]

The bottle, from the Legend of Zelda. So simple, yet it's probably one of the most useful items in the game.

The airship, from a lot of Final Fantasy games. Not sure if it counts as an item, but it's still really sweet when you finally get it. You feel like the world is your oyster, ya know?

The arm cannon upgrade, from any entry in the Mega Man X series. There are generally four capsules to find in each game; an armor upgrade, a helmet upgrade, a speed upgrade, and a firepower upgrade... But we all know that the most sought after is that last one. Aside from giving you the power to charge your enemy's stolen weapons, it lets you plow through smaller enemies that might have otherwise taken a while.

 

[Captain Wes]

Another day, another best item ever thread.

I predict 5 minutes before the chicken and the pulley from Monkey Island comes up.

Shit. ok, the abomination of nature for escape from monkey island

 

[PlasticPorter]

The Flying winged pirate ship from Golden Sun 2

 

[onethought99]

Keening and Sunder from Morrowind were priceless, I had no idea how I died the first time I found them and then found out later that they kill you if you dont equip the wraithguard first. Looking back on it now it was the funniest thing thats happened to me in gaming.

 

[Serious_Stalin]

Piccollo of the Flaming Fire, making people dance against their own will is amusing.
Maybe the Proxy gun from UT GOTY edition, or the Super Sheep from Worms.

 

[MisterDevil]

Nothing beats a box/crate of ammunition.

 

[SilentHunter7]

Phoenix Down. Capable of bringing back to life anyone.

But only if the plot allows it.

I remember fondly Twisted Metal 2, the British Character's special. It created a vortex that sucked all the other cars in, and then EXPLODES. On levels with 2 floors, it wasn't uncommon to get randomly sucked to the roof on occasion.

 

[stormcrow5]

Banana Bomb and the holy hand grenade from Worms

 

[LewsTherin]

hmmmmm........

[The Stoppable Force] i laughed when it dropped....and someone beat me to it

[A Steamy Romance Novel] another rediculous grey drop....you could read the first few pages, too.

 

[Vault_Dweller]

I'd say the BFG 9000 or the sheep from Worms.

Wow, everyone's using Vault Boy avatars.

 

[AgentSpliff]

Gravity Gun from Half Life 2. Yes I am a proper Half Life Fanboy