HOW TO VIEW PRIVATE PHOTOS ON FACEBOOK

First go to : 
http://apps.facebook.com/josh_owns/ 

Accept the app then you'll do anything you want : just copy/cut the ID, or the Name of the person and enjoy 

You can even download the entire album. if you dont want to visit each time http://apps.facebook.com/josh_owns/ 

There is an Mozilla addon that can do the task for you  .