[Techtalk] communication on own network

[Anne Wainwright]

Hi,

I want to be able to send someone on our network a small pop-up message
and get a reply if needed. Got to work both ways, must pop up on
whatever terminal the person is in or they can ignore it at will.

I don't want to be dependent on an outside server, this is just for
in-house so could be small thingy on our own server.

Generally running gui but could use terminal. Don't need the
complexity of an irc server, nor of a multi-messaging multi-protocol
utility to connect to the world's chat networks.

something with a 30second learning curve for affected users would be
great.

Can any one suggest something that might meet these simple needs,
please?

compliments of the season to everyone
Anne