We’ve been experimenting with this at our office. IM has not been a big thing before, but with a small new office, its a good way to learn. “iChat”:http://mactips.info/tips/2007/02/set-up-ichat is the builtin IM system in Mac OS X. It is a little confusing, because the default is to use mac.com addresses and connect into an AOL server. So the first thing you see is an AOL window and you wonder, what spyware brought this up. Also althought .mac addresses are free for this purpose few folks have them because they do such a heavy upsell of the $99 service and most folks (like me think that the .mac address is useless without the service).
Anyway, there are two other modes. One is with Jabber which is an open interface. Again this is confusing because when you add an account, they have something that says enter your gmail account and then you get a Jabber screen, so again doesn’t make too much sense and everyone needs to have a gmail account.
The best mode is Bonjour mode. This means that anyone in your LAN can IM you. You don’t need to sign on ahead of time. The big thing you need to do is to go into Setting and make sure that Security/Firewall is set to allow all incoming connections. Some folks turn it to allow only essential connections and then you can start Bonjour sessions, but no one can IM you.
Give it a try sometime though. Its the way all the 25 and under folks are doing it. It is way faster than email. Right now we are experimenting with Bonjour inside the firewall and gmail outside. Other nice thing is they have text-to-speech for when someone signs on and not, so you get presence. Not great if you have 100 people in your office, but great for the 5 person office.