The following bookmarklet works for me in Google Chrome:
Code:
javascript:window.location.href = 'http://youtube.com/get_video?video_id=' + yt.getConfig("SWF_ARGS")['video_id'] + "&sk=" + yt.getConfig("SWF_ARGS")['sk'] + '&t=' + yt.getConfig("SWF_ARGS")['t'];