In June, I began tracking the junk mail I was receiving. A plea to embark on Princess Cruises. Preapproved credit card offers from banks I'd never heard of. A furniture catalogue from Lulu and Georgia. Some weeks, more than a dozen pieces of unsolicited marketing mail - a.k.a. junk mail - clogged my mailbox. I'm not alone. Mail volumes in the United States peaked in 2011, but junk mail has continued almost unabated. Last year, roughly 63 billion catalogues, postcards, credit card offers and coup