This client library written in Ruby allows developers build headers for the SendGrid SMTP API in Ruby. The SendGrid SMTP API allows developers to deliver custom handling instructions for email. SendGrid is an email application.
Email-list.com provides email marketing and social media tools for businesses. Recently the company announced an Email List API that gives visitors to your website access to counts and quotes on email lists.
Email doesn't need postage, right? Is that old hoax about the postal service charging per message finally coming true? Not really. But PostageApp may be a service worth paying for if you want to send email from your application.