Instanciating

var Base = {
  _ops: {},
  _privateFnc: function () {},
  abstract: function () {},
  init: function (ops) {
    this._ops = ops || {};
    // INIT
  }
};

var Thing = (function () {
  var ThingBase = Object.create(Base);

  ThingBase = {
    abstract: function() {
      return this._ops;
    }
  };

  return function (ops) {
    var instance = Object.create(ThingBase);
    instance.init(ops);
    return instance;
  };
})();

var thingA = Thing(),
    thingB = Thing({foo:'bar'});

Re-arranged things a bit to cut down on object creation and get rid of the unnecessary closure. Of course I didn't test that at all :)

https://gist.github.com/734781

@xk oooops, true. I didn't notice... -_-

@xk @polotek, so basically you both get rid of the closure (actually makes sense) and have taken a similar approach. Thank you.