MozBackup

Great backup/recovery tool for Firefox and Thunderbird:

http://www.mozbackup.de/

Powered by ScribeFire.

ThunderBirthDay

In case you tend to forget people’s birthdays, here’s a great extension:

https://addons.mozilla.org/en-US/thunderbird/addon/5337

Thunderbird – Addressbook with Birthdays

I just found a great Thunderbird extension which enables additional fields to your contacts, such as birthday, etc.

Try it, it’s free. Unfortunately, it’s not available from the official Add-On-Site but here’s another source:

http://nic-nac-project.de/~kaosmos/morecols-en.html

Have fun!