You can message and share files inside your intranet without a server.
Home to the Signal Protocol and other cryptographic primitives
Distributed instant messaging system for developers
Secure communication software
Software per Call Center
Smoke: Android Crypto Chat Messenger
IXSF Messenger is a java-based messenger
Qiks is a LAN messnger to chat and transfer file esily.
GTK+ port of EZ Intranet Messenger
Chat Messenger written in Java
Underground IM is a free Java Instant Messaging solution.
a java based LAN messenger
small, fast, java messenger
Small messenger solution for teams inside a LAN using eclipse