With the fate of repetitive motion injury looming due to the need to drill 1,200 holes, [bitluni] took matters into his own hands and built this nifty DIY hole punch for light-gauge sheet metal.

Place holes in random locations about the paper. Make them a variety of sizes by using the single-hole punch, the pen or pencil, and the pin. Tack the black sheet to the front of the classroom to ...