Оповещение о новых сообщениях как на Яндекс.Почте

#mymess {font-size:10pt;padding:5px 6px;background:#000;opacity:0.7;width:auto;height:auto;bottom:0;left:0;position:fixed}  
#mymess:hover {opacity:0.8}  
#mymess a {font-size:1em;color:#dedede;text-decoration:none;}  
#mymess a:hover {color:#dedede;text-decoration:none;padding-top:10px}  
#mymess:hover #close {padding-left:9px;display: block !important;float:right}  
#mymess #close {display:none;font-weight:bold;cursor:pointer;color:#7c7c7c}  
#mymess #close:hover {color:#fff}

<?if($UNREAD_PM$>0)?>  
<div id="mymess">  
<div id="close" onclick="document.getElementById('mymess').style.display='none';return false">X</div>  
<a href='$PM_URL$'>You have a new message<?if($UNREAD_PM$>1)?>s<?endif?>!</a>  
</div>