Wired recently published an article about the discovery of a database containing 809 million total records exposed online. The MongoDB (freely available to hackers for some time now) contains 150 gigabytes of plain-text marketing data, including 763 unique email addresses.
These days it seems I get nearly as much phishing email as regular email. Setting aside the discussion of email being unproductive, at what point does the medium fail just because we stop believing any email we receive is legitimate? I'm already getting that way with nearly all of my vendors.