shaking image when hover

/**************************************************/
/* Image shake - Friendster Tweaks                */
/* by: Archer  - [url=http://www.friendsterforum.com%c2%a0/]www.friendsterforum.com [/url]        */
/* adjust the value of speed and radius          */
/**************************************************/

pics = document.getElementsByTagName('img')
FF = "Netscape"
IE = "Microsoft Interner Explorer"
radius=8
speed=5
a = 0

function tagAllPics(){
for(x=0; x<pics.length;x++){
if(navigator.appName==FF){
pics[x].setAttribute("onmouseover","tagX("+x+")")
pics[x].setAttribute("onmouseout","tagY("+x+")")
}

else{
psrc = pics[x].getAttribute("src")
pid = pics[x].getAttribute("id")
pcls = pics[x].getAttribute("class")
pics[x].outerHTML=
"<img id="+pid+" class="+pcls+" src="+psrc+
" onmouseover=tagX("+x+") onmouseout=tagY("+x+")>"}
}
}


function tagX(x){
pics[x].style.position="relative"
moveIt = setInterval("orbit("+x+")",5)
}

function tagY(x){
pics[x].style.top = "0"
pics[x].style.left= "0"
window.clearInterval(moveIt)
}

function orbit(x){
pics[x].style.top= radius*Math.cos(a/speed)
pics[x].style.left=radius*Math.sin(a/speed)
a++;}
setTimeout("tagAllPics()", 1000)