Så er det vel denne her, du har brug for:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"
http://www.w3.org/TR/html4/loose.dtd"><HTML>
<HEAD>
<TITLE>Resize til billede</TITLE>
<META NAME="keywords" CONTENT="roenving 2003;
http://www.eksperten.dk/spm/364403"><META NAME="Generator" CONTENT="Stone's WebWriter 3.5">
<SCRIPT LANGUAGE="javascript" TYPE="text/javascript">
function popWin(file){
newWin=window.open("","ResizeBillede","width=300,height=200,status=no");
txt='<HTML><HEAD><TITLE>Resize til bilede</TITLE><SCR'+'IPT LANGUAGE="javascript" TYPE="text/javascript">';
txt+='function resPic(){h=document.images[0].scrollHeight;w=document.images[0].scrollWidth;window.resizeTo(w+6,h+32);}</SCR'+'IPT></HEAD>';
txt+='<BODY STYLE="overflow:hidden;border:0px;margin:0px"><IMG SRC="'+file+'" STYLE="top:0px;left:0px;border:0px;" ONLOAD="resPic();"></BODY></HTML>';
newWin.document.write(txt);
newWin.document.close();
}
</SCRIPT>
</HEAD>
<BODY>
<A HREF="#" ONCLICK="popWin('../billede.jpg');return false;">klik her</A>
</BODY>
</HTML>