Joe Grand of Grand Idea Studio presents the backstory to his design of the Defcon 18 conference badge. (Joe’s talk actually begins at 09:05.)
The badge is based around a Freescale MC56F8006 16-bit digital signal controller and a Kent Displays 128-by-32 pixel reflective cholesteric liquid crystal display (ChLCD). Other functionality includes USB connectivity, seamless power switching, and hidden modes for a variety of contests held at the conference. Source code was developed using CodeWarrior for 56800/E Digital Signal Controllers. A single CR2032 3V Lithium coin cell battery provides the required power.
Joe has graciously posted the schematic, BOM, and all the tech docs related to this presentation.