dontforget/Guerrilla-SMTPd
Guerrilla SMTPd is minimalist, event-driven I/O, non-blocking SMTP server. The design goal and purpose of Guerrilla SMTPd is to receive large volumes of email and nothing much else. It happily gobbles down millions of emails every week on a single processor system. (Guerrilla SMTPd is running on GuerrillaMail.com - a temporary email address service). If you do invite Guerrilla SMTPd to your system, please remember to feed it with lots of spam, spam is what it likes best!