Check the ampCalDB FAQ . Also, you can define different stylesheets for each calendar so they can have unique appearances.
Administrative passwords can be different for each calendar to restrict calendar maintenance.
Included with ampCalDB are all the data entry screens required to administer the calendar. All from your web browser you can login, add calendar entries, edit calendar entries, and delete calendar entries. Just like with ampCal, you get every line of source code to the calendar. Plus, you also get all the supporting HTML and JavaScript ASP to change or update in any way you like. All attributes of ampCalDB are controlled by an external Cascading Style Sheet.