It is extremely important to use the “report a bad ad” link at the bottom of any boingboing.net page to report broken ads. That page has the correct configuration to collect the cookies used by ad providers so that our partners can track down the actual ads you saw.
Otherwise if you need to provide more detail -after using the link mentioned above_, you can email that info to badad@boingboing.net as well.
Thanks for the help in tracking these down.
