So far, I have used the chat with yahoo, google, skype and IRC. Fortunately now I have found one free chat service typically called Jabber Chat Service.
For Jabber Chat Service, you just go to and set up one account for jabber id in order to communicate with other people who use XMPP protocol chat client like google.
And then you can use your jabber id with PSI XMPP chat client or other XMPP chat client like SamePlace, Gtalk and so on.