My own context sensitive ads

Does anyone know of anything I can use to display my own context sensitive ads? Something I could use to advertise a particular, relevant product via data received from an affiliate feed?

Thanks!

you would need to learn a lot of javascript DOM

basically, you need to loop through tags, starting with body, ignoring anchors, etc, then using that information to run a query against some keywords database which is then related to the ad it self. then, if nothing matches, create default cases, etc etc.

lots of work :(

I'm guessing nobody has a handy script that does all that?

What about something easier, then - something php based that works on the first post of the thread before the page is served? Presumably the rest of the posts in the thread relate to the first post...

It would be a matter of grabbing the text of the first post in the thread and then determining whether any ads are associated with any of the words it contains, right?

PHP Code:

$postWords = explode(' ', $vbulletin->post[however you get the text of the post]); 

//get rid of noise words like the, is, if, it, he, she, etc.
$postWords = array_diff($postWords, $noiseWords);

foreach($postWords as $nextWordInPost)
{
  if($keywordsWithAds[$nextWordInPost] != '')
  {
    $ad = $keywordsWithAds[$nextWordInPost];
    break;
  }
 }

//provide for default case if we didn't find an ad
if($ad == '')
  $ad = $adsenseCode; 


Would there be a way to do this without it being too load intensive?