code: function(namespacedEvent, callback) {
        var event, namespace, _ref;
        _ref = namespacedEvent.split("."), event = _ref[0], namespace = _ref[1];
        if (namespace) {
          callback.__PIXIE || (callback.__PIXIE = {});
          callback.__PIXIE[namespace] = true;
        }
        eventCallbacks[event] || (eventCallbacks[event] = []);
        eventCallbacks[event].push(callback);
        return this;
      }
docs: Adds a function as an event listener.
  
  # this will call coolEventHandler after
  # yourObject.trigger "someCustomEvent" is called.
  yourObject.on "someCustomEvent", coolEventHandler
  
  #or
  yourObject.on "anotherCustomEvent", ->
  doSomething()
  
  @name on
  @methodOf Bindable#
  @param {String} event The event to listen to.
  @param {Function} callback The function to be called when the specified event
  is triggered.