onmousewheel="zoomImg(this)"

just putting this here for myself :P


function zoomImg(obj) {
var zoom=parseInt(obj.style.zoom,10) || 100;
zoom += event.wheelDelta / 24;
imgW = obj.clientWidth*zoom/100;
if (zoom>15 && imgW<1200) obj.style.zoom = zoom + "%";
return false;
}