I received this...Dear Adwords Advertiser.We are about to drain as much as we can, as fast as possible, from your Adwords Account.You have an Adword advertisement appearing on 'scraper' sites. Please be informed that although we have absolutely no intention of buying your product we intend to go to those sites as often as possible and click your Adword every time it appears.This will provide some nice extra income for that site but will soon deplete your Adwords account.We are doing this because we are a group that hates 'link-farms' and 'scraper' sites. it ends...Your best defense against this is to ensure your adword does not appear on any scraper sites. The easiest way to do this is to go into your Google Adwords Campaign Settings and turn off the 'Content Network' option.