Yep, it’s a QR code stencil generator! We present QR_STENCILER, a free, fully-automated utility which converts QR codes into vector-based stencil patterns suitable for laser-cutting. Additionally, we present QR_HOBO_CODES, a series of one hundred QR stencil designs which, covertly marked in urban spaces, may be used to warn people about danger or clue them into good situations. The QR_STENCILER and the QR_HOBO_CODES join the Adjustable Pie Chart Stencil in our suite of homebrew “infoviz graffiti” tools for locative and situated information display.