$ sudo grep -irl usbfs /etc
/etc/updatedb.conf
/etc/init.d/umountnfs.sh
/etc/init.d/umountfs
/etc/init.d/mtab.sh
/etc/init.d/mountkernfs.sh
/etc/rc0.d/S31umountnfs.sh
/etc/rc0.d/S40umountfs
/etc/rc6.d/S31umountnfs.sh
/etc/rc6.d/S40umountfs
/etc/rcS.d/S12mtab.sh
/etc/rcS.d/S02mountkernfs.sh
/etc/mtab
/etc/deluser.conf
/etc/udev/rules.d/udev.rules
/etc/udev/rules.d/020_permissions.rules
/etc/udev/permissions.rules
/etc/udev/udev.rules
/etc/udev/devfs.rules