Abstract: An improved sheet printer is provided capable of simultaneously printing both on a “main” surface of a sheet of print media and along edges of that same sheet of print media, such that when the sheets are stacked after being printed, a predetermined image will appear along one or more of the sides of the stack. The “side image” is formed by the dots that have been printed along the edges of the individual sheets. The side image is generated during image processing of the print job, not by a post-processing step of marking or printing against the side of a stack that has already been printed. The printer can form the side images by printing along all four edges of a single piece of the sheet media, and also on one of that sheet's main surfaces, during a single pass through a printing station.