In reply to Jon Brown.

Agreed—particularly on PostMan and leveraging Google Apps for SMTP.

Word of warning, though, if you do use Google: they'll block your account once you hit the limit. It think it was a ~48 hour block.

We had that happenen over Black Friday weekend and we had to scramble to find a new solution (we temporarily switched to a different Google email address/account and then got on Mandril).