Unobtrusively make backbone always fire 'success' and 'error' events.

Backbone.BaseModel.js

var _save = Backbone.Model.prototype.save;
var BaseModel = Backbone.Model.extend({

  save: function(attrs, options) {
    options || (options = {});
    var success = options.success;
    var model = this;
    // success doesn't have an event so always trigger
    options.success = function(resp, status, xhr) {
      model.trigger('success', model, resp, xhr);
      if (success) success(model, resp, xhr);
    };
    // error already fires event if no callback is given
    // so only modify backbone behavior if we have a 
    // callback
    if (options.error) {
      var error = options.error;
      options.error = function(model, resp, options) {
        model.trigger('error', model, rep, options);
        error(model, resp, options);
      };
    }
    _save.call(model, attrs, options);
  }

});