Blizzard has started offering a new verification service to Battle.net users which will allow folks to dial a toll-free-number to verify users’ location when unusual activity is recognized by the system.
The service has users register a phone number which can be used for verification purposes, no matter where you are located at the time. All one has to do is dial the toll-free-number from the registered digits if any strange activity is suspected.
This new service allows you to recognize immediately whether your account as been compromised in any way or, heaven forbid, your WoW account being stolen by hacks.
For more information on how this works, check out the Blizzard support page.