Ever got a »You have Mail«-Message in your terminal? If you’re an occasional command-line-user, this might confuse you as it did confuse me.
I recently did a fresh local WordPress-installation on my Mac for testing-purposes. Since then I got the message »You have Mail« whenever I started a new Terminal-session.
Turns out WordPress tried to send an E-Mail to the admins address. The delivery falied and the response ended up in the /var/mail folder.
So in case you want to get rid of »You have Mail«, empty your /var/mail folder.