Oooops....Apple did not tell its iCal customers that when they publish their iCal, anyone can view it. A simple advanced Google search limiting to the domain "ical.mac.com" brings up some interesting results. Sometimes you can find private addresses and phone numbers. Big security flaw.
By simply typing this into Google's search field, you can get some wild results:
Try it out. Not that I condone looking thru other people's personal stuff, but it is interesting none the less. I am just waiting for Google to take over the world ;)