BeeBEEP is an open-source, peer to peer, lan messenger that works on Windows, Mac OS, Linux, OS/2 and eComStation.
With BeeBEEP, you can talk and share files over local area network without a server. It supports offline messengers, messenger history, and messengers are encrypted based on Rijndael Algorithm.
For Windows and Mac OS, the official binaries are available for download at sourceforge.
How to Install BeeBEEP in Ubuntu:
For Ubuntu 16.04, Ubuntu 18.04, the latest BeeBEEP now is available as Snap package. Simply open Ubuntu Software, search for and install beebeep.
Or open terminal (Ctrl+Alt+T) and run command to install BeeBEEP snap package:
snap install beebeep
Once installed, open it from software launcher and enjoy!