I've discovered Firefox Sync a while ago, and it's absolutely awesome. Now of course I'd like most of my software to work this way! So is there a way to get the same behavior with Thunderbird?
There are a couple of options I have used:
EDIT: Contact sync software maintains a copy of your contacts somewhere and synchronizes your contacts to the that copy. The cycle is usually something like:
I am currently using gContactSync to sync my contacts.