This little program is awesome, you can save all your site definitions, passwords, testing servers, extensions and they work when you restore. I've dreamed of such a thing. Reformating my system never smelled so good!

It's free.
www.joexx.de/DW-Exporter/index_en.php

I am on a Mac. Since this is Windows only, how can I do this manually? Anyone know what files to back up, including serial numbers etc.