Why the Post Office Loves Junk Mail

"Direct mail, a.k.a. junk mail, is all that stuff we generally don’t want clogging up our mailbox – supermarket fliers, shopping catalogs, pre-approved credit-card applications. 'It has probably got the best return on investment of any kind of advertisement,' the U.S.P.S. Postmaster General Patrick Donahoe told me in an interview late last year."