Microsoft Windows 2000 Internet Information Server by Microsoft. Serves many protocols, including mail and news. UltimateIIS M-Store by MessagingDirect is a robust message server that delivers exceptional scalability, performance, and ease of operation. Features include a centrally managed, highly scalable universal message store accessible via IMAP4, POP3 or the web. Messages can be simultaneously accessed from several external processes.
Administration is performed locally, or remotely via a fully secure web administration tool.
Also has POP to SMTP gateway to allow collection from one ISP account. Netscape Messaging Server by Netscape. Netscape SuiteSpot Server includes Messaging Server as well as web and directory servers. N-Plex Internet Messaging Servers by Critical Path. PostMaster by Woppoware.