This is based on Debian Linux but should apply equally to any *nix distro.
Install LUKS/crypt-setup
apt-get install cryptsetup
Setup your LUKS Partition
Of course change /dev/md2 with whatever partition you intend to use LUKS on.
cryptsetup --verbose --verify-passphrase luksFormat /dev/md2
You'll be asked to verify your decryption password twice
*DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
E-mail (Thunderbird) with GnuPG encryptionThis is great tool for Mozilla Thunderbird which allows you to encrypt your e-mails so only you and the receiver can view it even if the e-mail is intercepting or obtained by another person.
The only small catch is that you of course have to install an extension to Thunderbird and then configure each account you want to use it with. Really it can probably all be done in a few minutes and the effort is worth it.........