TL;DR
Derek Woodroffe has created a unique badge that features a fully-functional scannable QR code, which is made up of 143 transistors. This badge serves a dual purpose: it functions as a promotional item for Extreme Kits and showcases a creative approach to integrating electronics in a visually interesting way. The QR code is not just an image but is constructed from MOSFET transistors that operate an 11-stage shift register to drive 24 colorful LEDs around the badge's edge.