Profanity has another cool feature that sets it apart from the native chats of Facebook and Google, namely Off-the-Record Messaging (OTR). This encryption protocol allows you to send secret messages to your friends that even Facebook or Google themselves wouldn't be able to decipher.
OTR support and plugins are available for many instant messaging applications, so it is by no means a requirement for your friends to run Profanity on a Raspberry Pi. Take a look at http://en.wikipedia.org/wiki/Off-the-Record_Messaging for a partial list of client software. The following are the steps to send secret messages:
The first thing we're going to do is generate your private key for the chat service over which you'd like to send encrypted messages, as each service requires its own key. You can think of the private key as something that will unlock your secret conversations.
Connect to your chat service of choice, then type the following command:
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