Staying within your Terms of Service for Pay-Per-Click advertising.

Here's a little trick to help you stay within your terms of service for your PPC (Pay-Per-Click) ad revenue.  PPC's require (I haven't found one that doesn't) that you not click on your own ads (i.e. Click Fraud).  You may have friends that come over that you let use your computer or your kid brings up the site, etc. 

The solution is to use a relative position div with two absolute position div children.  The children consist of a masking div and the ad div.  The masking div, which has a higher z-index than the ad div, contains a transparent gif that is set to the same dimensions as the ad content such as a banner or tower.

Then by using ColdFusion, wrap the masking div with a test of your choice, such as a CGI.REMOTE_HOST check, or perhaps a GetAuthUser() check.

<div id="overtureOuter" style="position: relative">
     <cfif CGI.REMOTE_ADDR eq "127.0.0.1" >
          <div id="overtureImage" style="position: absolute; top: 0px; left: 0px; z-index:99">
               <img src="/images/spacer.gif" height="600" width="120" onClick="alert('TOS Violation 
                 Prevention');"> 
        </div>
     </cfif>
        <div id="overtureContainer" style="position: absolute; top: 0px; left: 0px; z-index:98;">
              <script language="JavaScript">
                .... your publisher code here
               </script>
        </div>
</div>