getQueue: function(){
return queue;
},
I wouldn't want one to manipulate the queue outside if I were you. It could mess up your code. I suggest you return a copy of the queue, and not the queue array itself. Use slice to return a copy of the queue.
clear: function(){
queue = [];
return window.FnQueue;
},
A better way to clear an array without creating another array is to just set the length to zero.