HTML
<div id="navcontainer">
<ul id="navlist">
<li id="active"><a href="#" id="current">Item one</a></li>
<li><a href="#">Item two</a></li>
<li><a href="#">Item three</a></li>
<li><a href="#">Item four</a></li>
<li><a href="#">Item five</a></li>
</ul>
</div>

CSS
#navcontainer
{
font-family: Arial,Sans-Serif;
margin: 0 auto;
width: 70%;
border-bottom: 1px solid #ddd;
}

#navlist
{
width: 60%;
text-align: center;
margin: 0 auto;
padding: 0;
text-indent: 0;
list-style-type: none;
}

#navlist li
{
padding: 0;
margin: 0;
text-indent: 0;
display: inline;
}

#navlist li a
{
letter-spacing: -1px;
text-decoration: none;
color: #ccc;
font-size: 1em;
padding: 0 2px;
border-top: .5em solid #eee;
}

#navlist li a:hover,#navlist a#current
{
color: #333;
border-top: none;
font-size: 1.5em;
}

#navlist a#current { color: #fc6; }


ABOUT THE CODE
Some lists within the Listamatic site had to be modified so that they could work on Listamatic's simple list model. When in doubt, use the external resource first, or at least compare both models to see which one suits your needs.

FROM: http://CSS.maxdesign.com.au/listamatic/horizontal34.htm