According to their stuff, which is actually quite simple...
the CSS
Code:
#socializethis{background:#CCC;border:solid 1px #666;border-width:1px 0 0 1px;height:15px;width:260px;position:fixed;bottom:0;right:0;padding:2px 5px;overflow:hidden;-webkit-border-top-left-radius:12px;-moz-border-radius-topleft:12px;border-top-left-radius:12px;-moz-box-shadow:-3px -3px 3px rgba(0,0,0,0.5);-webkit-box-shadow:-3px -3px 3px rgba(0,0,0,0.5);box-shadow:-3px -3px 3px rgba(0,0,0,0.5);}
#socializethis a{float:left;width:32px;margin:3px 2px 2px 2px;padding:0;}
#socializethis span{float:left;margin:2px 3px;text-shadow:1px 1px 1px #FFF;color:#444;font-size:12px;}
The HTML
Code:
<div id="socializethis" style="opacity: 0.7; height: 35px; display: block; width: 260px;">
<span>
<div id="sicons">
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This is used for informational purposes only, if you do decide to replicate any copyright action, if any, i ma not responsible for, this was to show you how they did it