Secure instant messaging system for team collaboration
LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
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.
Standard Notes - A safe place for your notes, thoughts, and life's work
Bopup IM Suite - Organize secure messaging system and communicate instantly via self-hosted IM server.
Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.