This information is a bit antiquated but I plan to update it if I see increased demand for Jabber/XMPP alerts:
If you haven’t signed up for a Jabber account and are interested then please write us an email to admin@ with your current ES username and a password of your choice. We have tested several Jabber clients, so here is a list of our favorites:
For Windows there are a ton, so check the whole list. On OS X the list is a bit shorter but I like Psi – works like a charm. Usually all you have to do is to enter email@example.com as your login and the password you sent me in order to connect. A few clients require only the username and the server name separately but I’m sure you can figure it out – if you run into trouble please let us know.