PuTTY - Popular free terminal application. Mostly used as an SSH client.
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.
MobaXterm - Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more
MyChat - Secure instant messenger for any network
iTerm2 - A terminal emulator for macOS that does amazing things.
BORGChat - BORGChat is a LAN messaging software program.