I'm getting an intermittent problem which, when it occurs, absolutely 100% of the time means I have to reboot. No disk-related activites work. There is nothing in particular using up CPU time, but all the same applications are not useable (rainbow of death), and I can't even force quit applications.
I think this is possibly related to having an entry in /private/var/automount/Network - one time it seemed that there was a umount process that was stuck trying to unmount a network drive that didn't exist.
This has been reported to Apple, but I wondered if anyone else has had this problem ?