MailDrop - maildrop is a Mail delivery agent used by the Courier Mail Server. The maildrop MDA also includes filtering functionality. maildrop receives mail via stdin and delivers in both Maildir and mbox formats.

SpamTitan - Comprehensive Email Protection. 99.99% Spam Detection. Blocks phishing, viruses, malware and other email threats.

InboxKitten - An open-source, disposable email service 💌

MailCleaner - Cloud & on-premise anti spam software for businesses

Unroll.me - A cleaner inbox is just a click away! Unroll.Me gives you the tools you need to manage a cluttered mailbox full of pesky subscriptions emails.

Vade Secure - Email security to protect against email-borne phishing, spear phishing, malware, and ransomware. Email security and management based on artificial intelligence.