We are currently working with a security organization used by many major hosting providers in the US and UK. They have a system in place so that many providers can check regularly either manually or using automated tools to see IP addresses that are being used maliciously and what it is the have been reported or detected doing. We can then take whatever action necessary for each of the different types. Anything from notifying the server owner that a problem may exist or null routing the IP address automatically and flagging the issue for a staff member to deal with (like terminate the client or help them with their security problem).
Is there any chance that SpamCop can institute, even password protected using .htaccess style logins, a listing of problem IP addresses for each ASN or something similar?
Something like a list at, for example, http://www.spamcop.net/current/summary_report.php:
10.231.227.45 2007-04-04 10:41 Trap-10 Mole-0 User-1 Simp-0
10.85.54.231 2007-04-04 09:41 Trap-0 Mole-0 User-23 Simp-0
The content of that report would be different depending on who logged in to the protected page. Or perhaps you could share your data with this security organization so that they can include it in their reports?