My idea is a high powered, low rate of fire beam cannon of sorts. I am thinking it would be held like a mini gun at your side. It would fire a powerful beam that would be at least a foot or more wide. I think the sound of the alien ship death ray in MZ sounds perfect. It would be single shot, and instead of a reload animation it would be cool to have a meter that fills up to be like it has a capacitor that has to charge up before each shot with an appropriate sound accompanying it if that all is even possible. The shot would also have a small area of effect like the gauss rifle. Instead of making a new ammo it would just use more than one of another energy weapon ammo per shot. Which ammo it would need would be determined when balancing its power. Note that this wouldn't be a super weapon like a fat man, but maybe do 150-200 damage a shot. It would also have decent accuracy being a energy beam rather than a solid projectile.

I don't need any credit if anyone uses this idea, I would just love to have a beam cannon. I have looked around on Fallout Nexus and came up empty, and I think this mod would be decently popular.