Goodsync will allow you to backup and synchronize files. If you have not made, and do not make, copies of files as you should…this application might be good for you.
Synchronization will duplicate file changes in two folders; “backup” works in one direction only.
GoodSync can:
synchronize a notebook computer to a desktop computer, via a network and the internet…
keep user files in sync on work, and home, computers via a USB drive…
and incrementally copy files from the main hard drive, to a portable hard drive or another computer.
Windows Mobile phones and Pocket PC devices are supported.
RoboForm, Outlook, Outlook Express, Quickbooks, and ACT! are some programs it should work with.
There is a free version…the price is right for you to at least consider trying it: http://www.goodsync.com