public function user($username, $request) {
        $options = array(
            'info', 'videos', 'likes', 'appears_in',
            'all_videos', 'subscriptions', 'albums',
            'channels', 'groups', 'contacts_videos',
            'contacts_like'
        );
        if (!in_array($request, $options)) {
            throw new Garp_Service_Vimeo_Exception(
                'Invalid request. vailable options are ' . implode(', ', $options)
            );
        }
        return $this->request($username . '/' . $request);
    }