Life Hacker posted instructions on encrypting your Mozilla Thunderbird emails using GPG. This tutorial will get you up and running quickly with Thunderbird. There’s a description of what PGP is which isn’t the best we’ve seen, so this guide might be better for more experienced encryption users who just want to get it working in Thunderbird.

http://lifehacker.com/software/top/how-to-encrypt-your-email-180878.php