Mine would be Matildia from resident evil 4

MP5! What a question.

Grenade Launcher!!!!!!!!!!!!!!!!!!!!!!!!!!

The banana bomb in Worms !

the sheep launcher from Worms, although Mad Cow sure gives you quite a laugh. I would take the DY-357, the Laptop Gun and the Farsight from Perfect Dark, they all have their uses albeit their ammo is still limited in the end.

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Go play Wings 2: Aces High to understand one of the meanings for my name

Buster Sword from Crisis Core.

Dmc handguns!
and No more Heroes Tsubaki mach 1

zero's saber from megaman games

Might be the firebomb in Rise of the Triad. One of those 'Oh no, so many enemies! *fire* Hey, everybody's dead! Including me! That was effective!!!' sorts of weapons.

The Chainsaw-Your best friend and social interface with the undead.