Testing Barcode and QR Code Inputs with the EICAR String

HN commenters recommend it as an entertaining demonstration of how scanners and antivirus software fail on unexpected input.

A DEF CON 29 talk by Richard Henderson about encoding the EICAR antivirus test string into QR codes and barcodes and scanning them at real systems. Many systems that do not expect such input misbehave or collapse, including a parking garage system.