Separating and organising modules with objects?
I would recommend you use a closure like this:

var Obj = (function() {
    var privateState = null;
    return {
        A: 1,
        B: true,
        C: function() {
            return privateState;  
        }    
    };
})();


The biggest reason why this is a good idea is that it adds the ability to keep private state within the closure. Normally you can define private properties by convention but as the complexity of an object increases the better it is to keep certain things private.