A student showed up today with a drive formatted using exFat, which isn’t included on windows xp by default (Vista and Win 7 have support for it). Microsoft provides an update that can be downloaded. Here is the command line to allow you to do a silent install from a central location using psexec (Sysinternals):
psexec -c \\MachineName WindowsXP-KB955704-x86-ENU.exe /passive /norestart /quiet
It looks like it will require a restart to work, but can be installed without restarting right away.