Live Journal recently launched an LJ Jabber chat service. That means that we can all connect in real time using various chat programs and without having to sign up for other services.
My favourite way to use this is through the site Meebo.com. Logging in is very easy there. Once at the site go to the Jabber or GTalk login spot and use username@livejournal.com as your screen name and your LJ password as the password. Anyone that you list as a mutual friend on LJ will be on your list and ready to message.
Meebo is my default way to instant message now and I highly recommend signing up. With it you can login to all the major chat systems (AIM, MSN, ICQ, YIM, GTalk, Jabber) at once. Features are always improving and expanding, so most things you miss from a standard client should be on the way.
If you do give LJ chat a try, drop me a line so we can talk.