This URL Shortener: http://s-o.link, is built using the web2py framework. I built this web software to easily send tiny links for easy sharing over SMS, for various mobile apps that I build. In particular this mobile app: www.missedmybus.ca.
In this brief documentation for myself, I go over the process of sending GPG Encrypted emails in web2py. At the server level, there is a few things you need to do to install gnupgp and generate a public/private key with the email used for sending with web2py.