Along similar lines: http://www.mailgun.com/ http://www.mailgun.com/ http://postmarkapp.com/ http://postmarkapp.com/ And a couple of non-mail-related ones:

Along similar lines: http://www.mailgun.com/ http://www.mailgun.com/ http://postmarkapp.com/ http://postmarkapp.com/ And a couple of non-mail-related ones: http://www.fliptop.com/ http://www.fliptop.com/ - social intelligence API http://www.twilio.com http://www.twilio.com - SMS & IP Telephony API