Got into a discussion this morning with people at work and realized that I have never ever posted this here. I might have mentioned it once or twice, but now I'll just bring it up. 14.5 years ago I started this job I have and quickly realized that the company needed a way to communicate without having to get up and walk away from our desks. Now, understand that back in 2004 I was five years away from my first social media account. IM was a new thing to me and my requirement was to have an app that did not force me to create third party accounts. I knew this was possible because when I worked at the Desert Sun in Palm Springs, CA we could message each other. And that was a cross platform Microsoft based deal that IT had set up that worked in OS9. So. I found IP Messenger: http://ishwt.net/en/software/ipmsg/ IP Messenger allows you to create your own network ID. It sits in your menubar and you click on it when you want to send someone else on the network (who also has to be running IP Messenger) a message. It's got some away functionality and you can also send files using the app. It also works on Windows: https://ipmsg.org/en/ And, hell if you've got an iDevice: http://miwa.offside.ne.jp/ipmsg/index.html.en There is no requirement to create any kind of account. It just uses the network. On the PCs here in the shop I have it as a startup item so no one has to worry about starting it. It works on XP, Win7 and on up to Win10. I've never had any issues with it. It will ask to make it's own Firewall rules. Again, I know IM isn't much of a thing anymore, but if you do happen to need a cross-platform messaging system IP Messenger has worked flawlessly for me for the last 14 and a half years.