I'll show my age here, but back when email was new, there were two Administrative Assistants (secretaries, back then) that were using the distro list email as a chat device...
Literally, talking shit about EVERYONE in real time...
"Can you believe what Sheila's wearing to work today?" REPLY ALL
"Right? And did you hear that her and Roger are sleeping together?" REPLY ALL
It went on like this for several minutes and we enjoyed reading it, but someone finally put a stop to it. It was priceless!