I maintain several Linux servers at any given moment. Every server has postfix installed for sending emails, usually notifications or warning messages of some sort and most of these servers are professionally hosted allowing outbound emails with little to no configuration beyond installing postfix. However, my home server lies behind my ISP and they block all outbound emails citing SPAM as the reason. Regardless of their reasoning I had to find a workaround to allow me to send email notifications from behind my ISP. Well, it turns out this is rather painless with postfix and a Gmail account.