Put page numbers on both edges of the page

I just read a journal paper with the coolest feature: the page number on each page appeared in both the lower lefthand corner and the lower righthand corner. This meant that when I printed it out double-sided and stapled the corner, the page number was visible in the outside corner of every page despite the fact that the article happened to begin on an even-numbered page. (The benefit is smaller —but still beneficial— even when single-sided, as long as the pages wind up stapled or bound.)