JavaScript component to encode strings into QR codes. Works in both Node.js and the browser.
http://cryptocoinjs.com/modules/misc/qr-encode/
Most of the code:
Copyright (c) 2009 Kazuhiko Arase
URL: http://www.d-project.com/
Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
The word 'QR Code' is registered trademark of DENSO WAVE INCORPORATED http://www.denso-wave.com/qrcode/faqpatent-e.html
Some of the code / techniques from: