Draw with real metal!
Featured by Hackaday
This is a 3D printable marker for detailed electroplating / brush plating work.
It just requires some sponge / open cell foam soaked in an electrolyte and your plating metal.
Here is a video showing how it all works
There are different caps for different styles of anode (welding rods, wire and flat strip anodes, as well as a blank template for making your own.
It could even be used to make a normal marker.