Editing Additional Attributes of User Objects

How can I edit additional attributes for user objects in Active Directory Users and Computers?
As mentioned in my Add Additional Attributes to the User Objects article, an administrator can easily add additional attributes to existing object classes in the Active Directory Schema. Although extending the Schema is not for the faint of heart, and can easily wreck your AD infrastructure and ruin your entire forest, it is still something that can be achieved if one knows his way around and thoroughly tests his or her additions in a test environment, totally isolated from the production forest.
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