1. The Spartan Laser (Halo series XBOX)
The power of the sun in the palm of your hand.... or in this case, on your shoulder. Dirty Harry has his .44. His great, great, great, great (you get the idea) grandson, Master Chief has this. What other weapon would allow you to shoot through multiple enemies, multiple vehicles, multiple buildings and still have enough energy to nuke your popcorn 3000 miles away?
2. The Laptop Gun (Perfect Dark N64)
Its a laptop, its a gun, it has a 50 round magazine. What's more, in a rather novel innovation, its secondary function of this little beauty serves as a sentry gun. Who needs a secretary when you already have the perfect office assistant?