Weekend Learning: DBA_NETWORK_ACLS

Did you know that you can use the information in the views DBA_NETWORK_ACLS and DBA_NETWORK_ACL_PRIVILEGES to control access to your system?  Note 1634275.1 from My Oracle Support clued me in on it, as this gives us a script to reverse-engineer a solution in case the ACLs are ever lost and it clearly shows this access is controllable down to the user level.  I was talking about security for our system a few days ago, and this is yet one more way to help secure the system!