Here is something advertisers can check into: Detect click fraud. Nice site I just ran into: http://clickfraud247.com/
There are LOADS of programs out there. Many also offer conversion tracking. I turned in a click fraud report to Google 3 days ago. I had been in contact with my Account Manager who said to go ahead and send it in. Well, it's been 3 days and nothing. I had a LOT of click fraud instances in just a 7 day span and for only 1 campaign. I think they're either taking their time getting back to me, or, it's just a lot of data to parse. Detecting click fraud is easy, it's getting a refund which is hard.