div#s3slider {position:relative; width:180px; height:270px; margin:0 0 0 20px; overflow:hidden;}

ul#s3sliderContent {position:absolute; top:0; width:180px; margin:0;}

li.s3sliderImage {position:relative; display:none; float:left;}

li.s3sliderImage span {
   position: absolute; /* important */
   left: 0;
   font: 10px/15px Arial, Helvetica, sans-serif;
   padding: 10px 13px;
   width: 374px;
   background-color: #000;
   filter: alpha(opacity=70); /* here you can set the opacity of box with text */
   -moz-opacity: 0.7; /* here you can set the opacity of box with text */
   -khtml-opacity: 0.7; /* here you can set the opacity of box with text */
   opacity: 0.7; /* here you can set the opacity of box with text */
   color: #fff;
   display: none; /* important */
   top: 0;

   /*
       if you put
       top: 0; -> the box with text will be shown at the top of the image
       if you put
       bottom: 0; -> the box with text will be shown at the bottom of the image
   */
}