The Goo.gl URL Shortner not only makes long URLs shorter, it also gives you an option for a QR Code. I love this! It's so easy to use - just install the extension from the Web Store through your Chrome browser. The extension will appear at the top of your browser next to the Omnibox.
Just navigate to the website you want to shorten, then click the extension. It will provide you with the shortened URL and the QR code. Right click on the QR code to copy it - then you can paste it anywhere you want it.