And if you rivet them together by the corners in the holes, you get some really heavy, really nasty shuriken, too. Of course the practical use was to leave one riveted to a short section of the sickle bar, and use them to cut the strings on hay bales when feeding livestock in the winter. At one point, the crew on the ranch I worked on customized their own.

One was short-handled to fit in a pocket, one had a pitchfork tine welded on the back to help break up frozen bales, and mine had a blade on each side, because I was always setting it down and not paying attention when I picked it up.

Worked pretty well for throwing, too...