function showTeaser(el) {
	if (document.getElementById) {
		// reposition all teaser items out of sight
		for(var i = 0; i < document.getElementById('teasernav').childNodes.length; i++) {
			document.getElementById('teasernav').childNodes[i].style.top = '-3000px';
		}
		// show hovered element
		document.getElementById(el).style.top = '0px';
	}
}