A list of various weapons and their users. Using GMod you can make your own weapons. A big contraption creating community has popped up around GMod - creating such things as Rube Goldberg devices, catapults, cannons, bridges etc. Axis a wheel to it to create a working car. Take props from HL2/CS/DoD and weld them together to make walls.
The original bonemerge tool from GMod 12 now updated to work in GMod 13! This tool allows you to attach an entity to another entity using an effect called bonemerge.