MeetingAgenda Lite
Meeting Agenda Lite is a desktop sharing solution that allows users in an Intranet/Internet network to view remote computers. MeetingAgenda Lite comes with an inbuilt Instant Messenger that allows you to establish contacts with your Peers or Partners. ... Meeting Agenda enables you to share desktop and transfer files.
http://www.meetingagenda.net/meetingagenda_nj.exe - 4Mb - Download - Screenshot

Fomine Real-Time Communications Server
We offer you a really powerful solution for real-time communication over the Intranet. Not only will you be able to send instant messages inside your office or organization, but also maintain video and voice conversations, send files and share applications. ... That is why it is completely compatible with Windows Messenger. ... Fomine Real-Time Communication Server is based on the industry standard protocols.
http://www.fomine.com/products/frtcserver1.exe - 489Kb - Download - Screenshot

LanToucher Network Chat
LanToucher Network Chat is small and easy-to-use chat software for your small office or home LAN (Local Area Network). This easy-to-use LAN chat program with simple, intuitive user interface and a minimum of settings to adjust is an easy text communication solution for your small office LAN and... x/95/98/ME), Messenger service / 'net send' command (Windows NT/2000/XP/Server 2003), Samba smbclient (Unix/Linux), and a broad range of compatible instant messengers based on the standard SMB/CIFS protocol.
http://www.vitalsoundlab.com/files/ncsetup.exe - 709Kb - Download - Screenshot

LanTalk NET
LanTalk. NET Enterprise instant messenger for business networks. No setup, no administrator, no server. The program does everything on its own. It does not require a server. Instead, the program uses TCP/IP and UDC protocols, and port 2307 (by default), to make sure that there aren't any... Second, the program works with any network - Intranet, Internet, LAN, WAN, and VPN. ... Or what if one of your key employees is away on business or vacation, but wants so stay in touch? ... Instant messaging communication inside one office is great, but what if you need to discuss something with a...
http://www.cezeo.com/downloads/lantalk-net.exe - 779Kb - Download - Screenshot

ShixxNOTE
ShixxNOTE 6. net is a personal organizer, desktop sticky notes (post-it) program, instant messaging application (LAN messenger) and a communications tool used across a local network (Intranet), Internet and via e-mail. Easy to use personal info management application and powerful communication... Also you can export and import note(s) to or from file. ... You can set an alarm and expiration for any note. ... When you send note to other users, they will receive exactly the same note on their desktop if recipient have also program installed, otherwise program will use Windows Messaging...
http://www.shixxnote.com/download/shixnote.zip - 649Kb - Download - Screenshot

WebGate
Do you use pagers, mobile phones, or other wireless messaging devices at work? Do you want an easy way to let everyone in your company send messages to these devices from a web browser or via email? If so, WebGate by NotePage, Inc. is probably the perfect solution for you. ... ) or email client (MS Outlook, Netscape Messenger, Eudora, etc. ... ) and your company's intranet, or the Internet. ... ). ... WebGate can act as an internet mail server and receive email messages from any other standard email server (MS Exchange, Netscape, Unix sendmail, etc.
http://www.notepager.com/download/wgv3.exe - 4Mb - Download - Screenshot