The main idea is that smtpctl spf walk will read a list of domains from stdin and output a list of IP addresses and ranges to stdout, allowing it to be used in scripts, to generate file lists, or to be piped directly into pfctl to feed a table.
automx makes setting up a mail account easy. All your users need to provide is real name, mail address and password. Their mail client and automx will safely handle the rest.
Hastymail2 is a full featured IMAP/SMTP client written in PHP. Our goal is to create a fast, secure, compliant web mail client that has great usability. Hastymail2 is much more lightweight than most popular web based mail applications but still maintains a competitive feature set.
Sagator is an email antivirus/antispam gateway. It is an interface to the postfix, sendmail, or any other smtpd, which runs antivirus and/or spamchecker. It's modular architecture can use any combination of antivirus/spamchecker according to configuration.