Подменю

<script language="javascript">
function ShowHide(id)
{
if (document.getElementById('sm441612').style.display == "none"||document.all['sm441612'].visibility == "hidden"){
Show(id);
} else{
Hide(id);
}
}
function Show(id)
{
if (document.getElementById) {
itm = document.getElementById('sm441612')
itm.style.display = "block"
}
if (document.all){
itm = document.all['sm441612'];
itm.visibility = "show"
}
}
function Hide(id) {
if (document.getElementById) {
itm = document.getElementById('sm441612')
itm.style.display = "none"
}
if (document.all){
itm = document.all['sm441612'];
itm.visibility = "hidden"
}
}
</script>
<button onClick="ShowHide()"> Показать/скрыть>>></button>
<div style="display:none;" id="sm441612">
бла-бла-бла
</div>

<script type="text/javascript">
function SwitchMenu(obj){
if(document.getElementById){
var el = document.getElementById(obj);
if(el.style.display != "block"){
el.style.display = "block";
}else{
el.style.display = "none";
}
}
}
</script>

onClick="cont.style.display=''"

onClick="SwitchMenu('cont')"

<a href="javascript:SwitchMenu('cont')">Текстовая ссылка</a>