usb flash drive-folder synchronizing software

I am looking for software that will automatically synchronize lets say my documents folder with a corresponding folder on my flash drive.

Does anyone know of a program that can do this?

There are several, both free and commercial. The one I use the most on Windows is SyncToy[=http//www.microsoft.com/windowsxp/using/digitalphotography/prophoto/synctoy.mspx]SyncToy, it's a free utility by Microsoft.

Another I use is JFileSync[=http//jfilesync.sourceforge.net]JFileSync, because it's written in Java and runs on my Linux boxes as well, with a server mode to sync across a network connection. A bit overkill for routine use though, so I stick with SyncToy for the simple stuff.

I've used alwaysync - http//alwaysync.com/ with great success. I think it was a DMo suggestion. It's one of the few shareware softwares that I've purchased to support the developer.