Кусочек Вконтакта...

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<p id="back-top">
<a href="#top">TOP</a>
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background: url(/soc/toplink.gif") no-repeat scroll left 3px transparent;
color: #999999;
display: block;
font: 11px/100% Arial,Helvetica,sans-serif;
height: 14px;
padding-top: 10px;
text-align: center;
text-decoration: none;
text-transform: uppercase;
transition: all 1s ease 0s;
width: 80px;
}