] In a final report released July 31, the President's
] Commission on the U.S. Postal Service said sender
] identification technologies such as "personalized stamps"
] that embed digital identification information would not
] only improve mail tracking and delivery operations but
] would also enhance the security of the entire mail
] system.

No more anonymous mail.

U.S. Postal Service eyeing technology for 'smarter' mail - Computerworld