How Not to Send a Marketing Email

Sigh. I got a marketing email from a vendor today, along with 1538
other people whose email addresses were plunked right into the 'To:'
header. Microsoft needs to put an idiot dialog in Outlook that pops
up when you click 'Send' with more than five 'To:' addresses [0].

[0] http://slugmax.tx0.org/images/err.png