Apparently, the way XP works is that if it can’t find a ‘favorite’ WiFi hotspot, it automatically sets up the computer to broadcast itself as an ad hoc network point, using the name of the last connection the computer attempted. So… people see ‘Free Public WiFi’ and they try to log on. Then their own computer starts broadcasting the same thing, because it can’t find a network it knows. And, like a virus, the ‘Free Public WiFi’ that doesn’t work lives on and on and on.”

Nice eh?  So now you know.  And knowing is half the battle!