I find the use of search history for targeted ads a serious violation of my privacy.  I have tried to follow the official suggestions on http://www.google.com/support/accounts/bin/answer.py?hl=en&answer=54048.  I have turned off search history and cleared my browsers cookies.  Unfortunately I did not find "Disable customizations based on search activity" option, as I guess it has been removed from account settings.  I continue getting ads based on past searches.  I have tried searching the help center and the only question on the same topic is unanswered. How can I stop these ads?