clipped from: www.bumpower.com   

Say you’ve worked your arse off to create the killer landing page for the killer product. Your ppc is killing it and you are converting at a steady and hefty rate. Then all the sudden bam! Your conversions drop faster than anvil aimed at Wile E Coyote’s head. WTF is going on? Did you screw up your account or lander or something? Wrong! Dead wrong! Your landers been highjacked and some scumbag is now profiting from your hard work. This happens all the time. So what to do about it?


<script>
if(window.location.href.indexOf('yourwebsite.com') == -1)
{
window.location='http://yourwebsite.com';
}
</script>

This little bad boy checks to see if the lander is hosted on your site, if it isn’t then it re-directs to your site. IndexOf needs to be your domain, ie not blog.yourdomain.com just yourdomain.com.