I am using it to store and link information regarding my story settings. So I am putting all of my stuff for Avriet, Dakmir, Ealdru, Lenoir, The Devil's Due, and even the Paul stuff, over there. I wish this had existed during the time of Imperial Secrets, because it would have been an extremely useful research tool.
This is incredibly helpful because I can search by tags to find information I may have forgotten, like a minor character's last name, or the name of a flower, or the high priestess of a religion--I can put it all there, and it's at my fingertips. I can even cross-reference by using global tags such as 'magic' or 'diseases' if I can't remember which story a disease or type of magic goes with.
I love this! I suppose it's like a journal in a different format, but having the tag cloud on my main page makes it easier to access information quickly.