I just recieved an email from google. It seems google is in a class action settlement for failing to properly detect and stop click fraud on AdWords. All Adwords customers from January 2002 to present are able to join, and receive a possible settlement with advertising credits. More information here: clicksettlement.com

Google's made an official announcement on this topic. You can check it out here:
http://adwords.blogspot.com/2006/05/lanes-gifts-v-google-settlement.html