This is a dirty solution; but works. A good approach would be to use libudev.
On inserting an USB drive, automounts the drive at /media/ as a directory named by device label; just the device name if label is empty: /media/usbtest, /media/sdd
Tracks the list of mounted drives in /var/log/usb-mount.track.
Logs the actions in /var/log/messages with tag 'usb-mount.sh'
Please do not expect it to perfectly handle all your needs. Be warned, minimally tested; okay for temporary plug-ins but certainly not recommended for enclosures with longer TTL.
To setup, run CONFIGURE.sh with sudo or as root; REMOVE.sh to undo the
setup.