They are NOT COMPLEX AT ALL!
Code:
<html>
<head>
<script type="text/javascript">
function drop_down(item_number)
{
var obj = document.getElementById('item'+ item_number);
if (obj.style.display == "block")
{
obj.style.display = "none";
}
else
{
obj.style.display = "block";
}
}
</script>
</head>
<body>
<div id="menu">
<a href="javascript:drop_down('1');" onMouseOver="drop_down('1');" onClick="drop_down('1');">[mouse me over]</a>
<div id="item1" style="display: none;" onMouseOut="drop_down('1');">
<a href="#">Link 1</a><br />
<a href="#">Link 2</a><br />
<a href="#">Link 3</a><br />
<a href="#">Link 4</a><br />
</div>
</div>
</body>
</html>
Correct me if I'm wrong.