Decorate $firebaseArray to provide a destroy function.

decorate_service.js

(function() {
  // store a list of open refs
  var openItems = [];

  app.config(function($provide) {
    // when creating a $firebaseArray, record the ref so we can destroy it later  
    $provide.decorator("$firebaseArray", function($delegate) {
      return function(ref) {
        var list = $delegate(ref);
        openItems.push(list);
        return list;
      };
    });
    
    // when calling unauth, call destroy on all refs
    $provide.decorator('$firebaseAuth', function($delegate) {
      var _super = $delegate.
      return $delegate;
    });
  });
  
  app.factory('destroyAllRefs', function() {
    return function() {
      // when this factory is called, invoke $destroy on open refs
      angular.forEach(openItems, function(item) {
        item.$destroy();        
      });
    };
  });
})();

How would this be done for a $firebaseObject?

@RyanWarner - I ended up figuring it out and had to support both $firebaseObject and $firebaseArray - https://gist.github.com/meetbryce/614104cf5b09f2a868b399b29a1e20fa