What is your favorite gun ever in video game history?

[telly]

I don't really do gun games... um... the thing from Rachet & Clank that fired chickens? Or did it turn enemies into chickens? Either way, the chicken one!

There was a gun that turned your enemies into sheep in Going Commando, that was fun

[arkaneer]

I'm pretty sure Lost Planet had a gun that fired sharks 

Edit - I was actually thinking of Armed & Dangerous on the Xbox:

[turf]

The Cow Launcher from South Park on the N64.

When you got shot with it in multiplayer you could see rectum slide down to cover your screen.  It still cracks me up.

[wvdoom]

Light gun: Konami Justifier
Game gun: eeeh pretty much any shotgun, or scarborough fair