## The Gennai Pen SL01 Is Closer to Clockwork Than Stationery Press a button on most pens, and you get ink. Press the lever on the Gennai Pen SL01, though, and you get mechanical theater instead. This stainless steel ballpoint, designed by Japanese artist Hidetoshi Nakayama and built by TACTICALGEEK, swaps the usual click-to-retract routine for a lever borrowed from telegraph keys. It’s a pen that behaves like a tiny machine, and that’s exactly the point. Nakayama built his reputation on a specific look: mechanical steampunk, heavy on exposed screws, stacked metal layers, and hardware that…