1 January 2012 was the last day with possibility to legally unlock phones with Windows Phone 7 with ChevronWP7 Labs. That day has been sold the last of the 10000 Tokens, which allowed to unlock phone for only 9$. Thus, the only legal way to unlock your phone is in an account on AppHub. Unfortunately, such an account cost 99$. At the moment there are no plans to reactivate the project.