Besides Office Communicator there are a couple of other rather essential tools you just need to have to stay connected to the world.
Both of them are available for the Mac:
Skype
Even though Skype still uses a closed proprietary protocol for its communication, I find it an easy way to keep in tough with people both in the Netherlands and abroad. I sometimes use the Unyte Application Sharing plugin to give some remote support. The plugin itself isn’t available for Max OS X though.
But still it an essential application to have installed.
Twitterific
OK, I admit it, this shouldn’t be one of the first tools to install on a new Macbook, but it is. Even though I’m not a hardcore Twitter addict, I went looking for a Twitter tool right away.
I hadn’t used it before, because there isn’t a Windows version for this particular tool, but I liked Twitterific right away. It is hidden when there are no new tweets, and pops up when needed.