I know it's limited to 147 characters, but if all you want is simple messaging then that might fit the bill.
Not that I've used it myself. May be others here will have better ideas.
Mark
I've been using squiggle lan messenger and love it; but the problem is our staff is starting to become more and more mobile. I basically want the same thing but that allows us to be on different networks. I really don't want to use yahoo, gtalk, aim, skype, etc as those appear very unprofessional and people become sidetracked with personal contacts. I want a very simple messnger/chat system for my staff and I. I have a domain and storage so I could host it myself... I'm open to ideas.
Thanks Cnet!

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