Is there a program that I can run from my NT Server that would essentially allow each machine to communicate to each other in a speedy amount of time?

(i.e., small office, but would like to rid phone message paper with messages through our LAN ... but quicker and easier than email? ... and keep a history? .. we have 1 -NT4 Server, 1-NT6 WorkStation, 1-W98 WorkStation, and 1-W95 WorkStation)

Thanks



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