Cool!
I need to check out my local REWE Storefronts :)

XSS, SQL Injection and Fuzzing Bar Code Cheat Sheet
http://www.irongeek.com/xss-sql-injection-fuzzing-barcode-generator.php

XSS, SQL Injection and Fuzzing Bar Code Cheat Sheet

Irongeek's Information Security site with tutorials, articles and other information.

@overflo
I will check it out next time at an airport