BusinessMail4 email server - From the developer: "BusinessMail 4 is a powerful multi threaded Intranet/Internet email server designed specifically for the business environment. It can be installed on any W95/W98//ME/W2K/XP or NT4 PC, and does not require a dedicated PC for smaller installations. BusinessMail 4 offers single and multiple email domain support, a built-in web mail interface, built-in user configurable anti-spam address and subject/body matching systems, user & domain aliasing, powerful routing/filtering, flexible connection scheduling, remote administration via simple emails, support for permanent connections such as ADSL, Roadrunner and other cable modems, and of course all types of dial-up connections, automatic SMTP mail collection (if you have a permanent Internet connection and an MX record) and also via POP3 from multiple pop3 mailboxes. "BusinessMail 4 can even send mail directly to internet recipients without an SMTP relay (using MX records), making it perfect for DSL, RoadRunner and other permanent connection users that are hosting their own Internet domains. BusinessMail can even deliver mail from any configured mailboxes to that mailbox owners email client system if they have an SMTP server running on the client PC. BusinessMail 4 provides support for user configurable ports to allow it to connect across your network via internal or external routers, cable modems, dial-up systems or T1/T3 connections."