<script>          
          jQuery(function(){          
          $("#banners img").hover(function(){          
          $(this).stop().animate({opacity:'1.0'})},          
          function(){$(this).stop().animate({opaci ty:'.3'} )}          
          );          
          });          
          </script>          
          <style>          
          #banners img{opacity:.3;filter:alpha(opacity=30)}          
          </style>          
          <div id="banners">          
Ваши баннеры         
          </div>