<script type="text/javascript" language="javascript">
//<![CDATA[

window.onload=function()
{
document.getElementById("d2").onclick = slideIt;
document.getElementById("d3").onclick = slideIn;
};

function slideIt()
{

var slidingDiv = document.getElementById("d1");
var stopPosition = 1;

if (parseInt(slidingDiv.style.left) < stopPosition )
{
slidingDiv.style.left = parseInt(slidingDiv.style.left) + 6 + "px";
setTimeout(slideIt, 1);
}
}

function slideIn()
{

var slidingDiv = document.getElementById("d1");
var stopPosition = -50;


if (parseInt(slidingDiv.style.left) > stopPosition )
{
slidingDiv.style.left = parseInt(slidingDiv.style.left) - 6 + "px";
setTimeout(slideIn, 1);
}

}
//]]>
</script>


<div id="d1" style="position:absolute; left:-50px; top:0px">
<div id="d2" >открыть/div>
<div id="d3" >закрыть</div>
</div>