2. Hammer of Dawn - Gears of War
This was the weapon that turned me from a kid to a man when playing games. The sheer enormity of the thing, plus the amount of build up included made it the gaming equivalent to a date with Kayley Cuoco. Despite the fact it's over almost before you've began doesn't take away any gloss. The destruction you can cause with a satellite tracking laser gun is insanely great. When I fought Queen Myrrah at the end of number 3, how happy I was to see an almost unlimited amount of H.O.D's.
3. Portal Gun - Portal
Ok, so technically not a weapon in the traditional sense, but still completely awesome. Imagine shooting portals at will and reappearing through them. This game, largely owing to this badass gun, is how my Utopian world would look bar the crazy robot trying to kill me. This would be perfect for those times where your parents 'ground' you. For everyone's sins, we'll never get to see a life-like replica.