var timer = 0;
var lastid = -1;

function show(id)
{
    clearTimeout(timer);
    if( lastid != id)
    {
        lastid = id;
        document.getElementById('popup').innerHTML = document.getElementById('menu'+id).innerHTML;
    }
}

function hideAll()
{
    timer = setTimeout("document.getElementById('popup').innerHTML = ''; lastid = -1;", 250);
}