LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
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BORGChat - BORGChat is a LAN messaging software program.
Ubiq Security - Enable developers to build encryption into apps in minutes
Softros LAN messenger - LAN messenger for an internal office chat for home or business users. It does not require a server and is very easy to install and use. It supports personal chats, group chats, message brodcasting, files transfer and remote desktop access.