Rated 5 out of 5 stars
I can't believe this add-on has no reviews yet...
This is a companion add-on to the program 'MyPhoneExplorer'. This program allows you to sync all of your contacts, calendars, tasks and more with your android mobile phone and Thunderbird.
This is the only free software I've found that allows me to sync via a USB cable with all of my locally stored information.
The add-on itself mostly runs in the background and works with the desktop program.