MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Proxmox Mail Gateway - Protect mail server against spam, viruses and malware with Proxmox Mail Gateway security for businesses, government, education and non-profit organizations.
Constant Contact - Constant Contact offers email marketing, social media marketing, online survey, event marketing, digital storefronts, and local deals tools.
SpamAssassin - Use this program to "Unspam" your mailbox(es).
Brevo - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.
Rspamd - Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...