When it comes to sending emails, if you are using a commercial provider that has been linked to the PRISM spy initiative, you can throw a spanner in the NSA's works by learning how to send and receive encrypted emails. PGP or its free cousin GPG are considered the standard for email security, and these can be used to both encrypt and decrypt messages - meaning you can thwart surveillance unless you are unlucky enough to have Trojan spyware installed on your computer.

Novice computer users learning how to use PGP or GPG may find it daunting at first, but there are plenty of tutorials online for both Mac and Windows users that can help guide you through the process. For journalists working with confidential sources, attorneys seeking to ensure attorney-client privilege, or others whose work requires secure communications, learning how to use PGP or GPG is an absolute necessity. Organisations seeking to protect themselves from email grabs could go one step further: they could take more control of their messages by setting up their own email server instead of relying on a third-party service, helping ensure no secret court orders can be filed to gain covert access to confidential files. And if you need to store private documents online, you can use Cloudfogger in conjunction with Dropbox.

For instant messaging and online phone or video chats, you can avoid Microsoft and Google services such as Skype and G chat by adopting more secure alternatives. Jitsi can be used for peer-to-peer encrypted video calls, and for encrypted instant message chats you can try using an "off the record" plugin with Pidgin for Windows users or Adium for Mac. Like using PGP encryption, both Pidgin and Adium can take a little bit of work to set up - but there are tutorials to help ease the pain, such as this for setting up Adium and this tutorial for Pidgin.

As for phone calls, if you want to shield against eavesdropping or stop the NSA obtaining records of who you are calling and when, there are a few options. You could use an encryption app such as Silent Circle to make and receive encrypted calls and send encrypted texts and files, though your communications will be fully secure only if both parties to the call, text or file transfer are using the app. Other than Silent Circle, you could try RedPhone (Android and iOS) for making encrypted calls or TextSecure for sending encrypted texts.