hash.js

String.prototype.hashCode = function(){
                  var hash = 0;
                  if (this.length == 0) return hash;
                  for (i = 0; i < this.length; i++) {
                    char = this.charCodeAt(i);
                    hash = ((hash<<5)-hash)+char;
                    hash = hash & hash; // Convert to 32bit integer
                  }
                return hash;
                }