I had a computer problem at work, so I checked a recent email with the new group address we were submitting problems to. I sent it and within 5 min my email began filling up with unfamiliar addresses, all saying some variant of 'I don't think this email's for me'. Turns out the group address included the group 'all people the company's dealt with ever'. So lots of people from all kinds of state organizations and companies. And none of it was my fault, but I had to apologize to everyone who emailed back.