Before using the script, change the three instances of mycompany.com in the script to match your own company or school.
[robg adds: Due to some very wide lines that weren't easily breakable, I've uploaded the script to the macosxhints' downloads folder. Click the link to open the script in a new window, from where you can copy and paste it into a Terminal editor. Remember to make it executable (chmod 755 script_name), and setting it up as a cron task is left as an exercise for the reader...]

