Google Voice Extends Free Calling To Hawaii And Alaska

Google Voice now covers all 50 states with it's free calling offering to registered users.

You can initiate free calls to Alaska and Hawaii from your inbox online, from our mobile apps, or by dialing your own Google Voice number from one of your phones and selecting option 2 to place a call. You can also forward calls to your Google Voice number to Alaskan or Hawaiian phones for free.

Google Voice is only available in the US, and you are required to have a working US phone to setup a Google Voice account.
Google Voice Blog: Free calling now to Hawaii and Alaska