Pop-ups in Adwords landing pages

Adwords guidelines state that you as an Adwords advertiser shall not have any pop-ups, pop-unders or any kind of window that opens from the landing pages. Google says this is because of the 'bad user experience' in the past.

Google further says, irrespective of the intent of the pop window, the user dislikes a popping window. Because of this reason, Google forbids Adwords advertisers from using popups of any kind on their window. So, even if the pop up was for a charity, it is still a firm NO with Google.

Adwords says this all here