I want to communicate instantly via text with two people in another room on the same local network. They are both on Macs. I am on Windows. I would like their windows to be scalable to personal preference & "always on top". I want to use the local network as opposed to a third party that will send the data up & down an internet pipe &/or bill us. I'd prefer it to not make sounds, or at least be able to disable sounds.
What are my options?
^I want to use the local network.
just use google hangouts
here is another option
LAN Messenger
An intranet chat application that does not require a server.
https://sourceforge.net/projects/lanmsngr/
http://www.r2.com.au/page/products/show/tonic/
this seems to be another one.
i have not used any of these so i don't know the details i just googled the shit
Yes, I do know how to use google but am looking for direct experience here. Thanks, though.
Didn't there used to be one built into windows 
I like Slack