USB Backup Options

Objective: easy-bake scheduled backups over the network to a USB key.
I narrowed the search down to SyncToy for XP or ROBOCOPY.

SyncToy: once set up (use the Echo option for one-way backups) you could script it:

cd\
cd C:\Program Files\Microsoft\SyncToy\
SyncToy -R "Test"

And kick the above off with Scheduled Tasks. However I found that if you delete files on the USB key they aren't automatically replaced again.

Onto ROBOCOPY, which is part of the 2003 Server Resource kit. Here's a sample script for sample script for mirroring data (see http://www.ss64.com/nt/robocopy.html for more). Again kick the below off with Scheduled Tasks

@ECHO OFF
SETLOCAL

SET _source= "\\Server1\$hared\My Stuff"

SET _dest= "C:\Documents and Settings\Galactus\Desktop\My Stuff"

SET _what=/COPYALL /B /SEC /MIR
:: /COPYALL :: COPY ALL file info
:: /B :: copy files in Backup mode.
:: /SEC :: copy files with SECurity
:: /MIR :: MIRror a directory tree

SET _options=/R:0 /W:0 /LOG:MyLogfile.txt /NFL /NDL
:: /R:n :: number of Retries
:: /W:n :: Wait time between retries
:: /LOG :: Output log file
:: /NFL :: No file logging
:: /NDL :: No dir logging

ROBOCOPY %_source% %_dest% %_what% %_options%

So ROBOCOPY by a nose. Both SyncToy and ROBOCOPY did allow backup of open files (at least they did in my testing) as well as backing up the newer version of a file.