I found FolderShare to be easy to use. It instantly synchronized my designated files between my Internet-connected laptop and desktop PCs. I've experienced no problems with it whatsoever.
To begin, you download the FolderShare Satellite software onto each computer you want to synchronize. During installation, you create a FolderShare account with a user ID and password. After installation, click the FolderShare icon in the system tray, log in to your FolderShare account, and select each folder that you want to sync (one at a time).
Once FolderShare is installed on both your Internet-connected computers, any change made to a file in a FolderShare folder on one PC is automatically synced on the other. The changes happen in the background. If you make changes to a file while one computer is offline, the changes are synced as soon as the second computer has been reconnected to the Internet.
FolderShare will mirror selected folders from one computer onto one or more secondary computers, including your My Documents folder. There's no need to set up identical file structures between the computers you want to synchronize.
FolderShare has some limitations. Files larger than 2GB in size can't be synced, according to Microsoft. Also, you can create up to ten folders with up to 10,000 files each. While that's an extremely generous limit that few people would exceed, it's not unlimited.
Also, it's cumbersome to synchronize Microsoft Outlook between computers, though it is possible. File conflicts can occur if you have Outlook open on more than one synced computer at a time, and FolderShare can't merge existing Outlook data from different computers. One PC must be designated the "master" Outlook source.
As a workaround, I use Migo software on a USB thumb drive. Migo creates a profile of my desktop PC, which includes my Outlook data, among other things. The profile is stored on the USB drive. The net effect: After Migo synchronizes my profile on the USB drive, I can then access the data within that profile easily just by plugging the drive into my notebook's USB port. It's an easy, simple way to carry your most recent Outlook e-mail and other items from one computer to another, and back again.