LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
Stork.ai - AI-Based Collaboration for Hybrid Teams. Rich media messaging, advanced video and voice conferencing, auto-transcribing and screen sharing. Serendipitous meetings at the water-cooler with your human and AI teammates.
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.
Ring4 Meeting - Dead simple video conferencing - free, in browser
MyChat - Secure instant messenger for any network
Suttna - Keep every team member in the loop