Secure mail server with anti-virus & anti-spam, built-in firewall and proxy for controlled Internet sharing. 5 user version is free for commercial and non-commercial use!

Mady MTA Service is a small and easy SMTP server. It's small, stable and fast. It can use in a small LAN or home network and provide mail deliver service for a small group of users.

Akeni LAN Messenger is a cross-platform (Windows and Linux) instant messenger for LAN.

netMailshar is an easy-to-use, powerful mail server that enables every computer in an office to send and receive email not only across the Internet but also within a LAN. It provides centralized, generic protection against all email viruses.

Data replication, backup and synchronization software for networks. LAN, HTTP, FTP, E-mail support. Has flexible scheduler settings and numerous file transfer functions.

Firewall, proxy, and mail server gives the complete solution of shared access.

Allows users to monitor events recorded in the Application, Security, System logs, dispatches the notifications about events via LAN, which can be received by the Windows NT4/2000 Messenger service, and using e-mail, SMS and ICQ (via e-mail gates).

LanTalk.NET office instant LAN messenger that work in LAN, WAN or Internet, without any server or internet access! Designed for business networks. In fact, in most companies LanTalk.NET replaced corporate e-mail for exchanging files and messages.