An example where I was using promises all wrong...

promise-mistake-before.js

var fs = require('fs');
var getConfig = function() {
  // Using promises because fs.readFile() is async
  var deferred = Q.defer();
  fs.readFile(__dirname + '/../../aFile.conf', 'utf-8', function(err, data) {
    if (err) {
      deferred.reject(err);
    }
    var configJSON = helpers.config2JSON(data, true); // true indicates we are parsing the input section
    deferred.resolve(configJSON);
  });
  return deferred.promise;
};