LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
Spike - Spike solves businesses' communication chaos by bringing together email, team chat, collaborative docs, and meetings, into one feed.
Bopup IM Suite - Organize secure messaging system and communicate instantly via self-hosted IM server.
Seald - Keep your conversations secure, everywhere.
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.
ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.