In the mid-1980s, Mike Sandau and his friend connected their
Atari 8-bit computers to their citizens band radios to create a
small radio-telephone computer network. Their "DIALOG" project
combined the radio hardware with custom software (first in Atari
BASIC, then later in Action!) to allow chatting, broadcasting
messages, and binary file transfers over the air.
Mike has uploaded the software, source code, and screenshots
to the Internet Archive, and placed it in the public
domain.