public static function createInstance($driver, $options, $prefix = '')
    {
        if(!in_array($driver, self::$_validDrivers)) {
            throw new \Exception("Driver '{$driver}' not implemented");
        }

        $class = __NAMESPACE__ . '\\Driver\\' . $driver;

        $driver = new $class;
        $driver
            ->setOptions($options)
            ->setPrefix($prefix);

        return new Mcache($driver);
    }