All the different search engines reveal to me what people are
searching on when they come to my site. I use Jim Flanagan's Search
Referral Zeitgeist program to graphically depict the most popular
search terms.
Although Jim and his domain seem to have dropped off the net, you can still get his code to do this on your own site.
The name for Oz in the "Wizard of Oz" was thought up when the creator, Frank Baum, looked at his filing cabinet and saw A-N, and O-Z; hence the name "OZ".