http://nguipxnkrp3qrzrlduhsatpcpwehnblzmlkc5ifiumxq4z5jlh4lwvid.onion/os_archive/os_OPSEC_357.html
Personal and sensitive communications should be made face to face, or signaled using gpg or through other encrypted communications methods. Make sure the person you're talking to isn't a retard carrying a cellphone in their jacket pocket, and make sure to ask them about this before you start your conversations, and if they have a cellphone tell them to turn it off and remove the battery before you start your conversation....