Top 50 Bad Hosts & Networks 2009

http://hostexploit.com/index.php?option=com_content&view=article&id=201
   &Itemid=106

AS23456 will just continue to grow I guess, but considering the quite few networks with 32bit ASN I guesss it might be an advantage for some abusing networks to actually get this as some tracking tools doesn't seem to support it and it's thus harder to find the responsible network.