The Battle.net Mobile Authenticator is now available as a free download for Windows Phone 7 devices on the Windows Phone Marketplace. According to Blizzard, the Battle.net Mobile Authenticator provides a one-time password that you can use in addition to your regular account name and password when you log in to a Battle.net account to play World of Warcraft or StarCraft II. The Battle.net Mobile Authenticator is already available for other mobile devices such as iPhone, Blackberry, and Android.

You can also purchase a physical Battle.net Authenticator from the Blizzard Store.

Check out www.battle.net/security more details.