It has actually been some time since I added it, but I've forgotten to write about it.
If you go to your account page, you'll find "Event notification" in the bottom box. If you submit an XMPP address (such as a GTalk or jabber.org account), you will be sent notifications of in-game events that you may care about. Currently, events being sent are people trespassing on your claim and you being force summoned.
This is mostly an experiment, partly to see if my XMPP daemon works as it should, and partly to see what effect it has on crimes being done while the victim is offline.