BeeChat.Network is free and open source software allowing legal (<1 watt or 100mW @ 2.4GHz or 868 MHz) license-free, mesh network radio communications in an encrypted manner without the Internet.
It works by plugging a Digi XBee dongle into your USB port to turn your machine into a node in the mesh network, allowing you to transmit data such as files, and even chat with other nodes.
