Today we saw the first release of USBSink:
USBSink is a GNOME program for file synchronization over USB.
It is designed for users of removable drives, such as flash drives
or external hard disks. The goal is to have a complete automation of
data trasfers, after a task has been defined. With file monitoring and
hardware detection features, USBSink is able to respond and act
according to relevant events across the desktop.
I'm surprised nobody's created this utility before, and thankful someone finally has. (How long have USB flash drives been around for?)
There's two screenshots available as well as some basic development plans.
If looking for a useful utility to synchronize files to a USB drive, this is the answer to your prayers - Give it a download!