Email Testing for QA & Development Teams. Catch every email your product sends, analyze it's contents, follow links and test deliverability all via the Mailosaur API.
MailCatcher runs a super simple SMTP server which catches any message sent to it to display in a web interface. Run mailcatcher, set your favourite app to deliver to smtp://127.0.0.1:1025 instead of your default SMTP server, then check out http://127.0.0.
Dummy SMTP server that sits in the system tray and does not deliver the received messages. The received messages can be quickly viewed, saved and the source/structure inspected. Useful for testing/debugging software that generates email.
Ethereal is a fake SMTP service, mostly aimed at Nodemailer users (but not limited to). It's a completely free anti-transactional email service where messages never get delivered.
Sendria (formerly MailTrap) is a SMTP server designed to run in your dev/test environment, that is designed to catch any email you or your application is sending, and display it in a web interface instead of sending to real world.