malwaredomains.schulte.org
This is a DNS-based RHSBL list, compiled from a number of sources.
You can use this list with any service that understands RHSBL logic.
For example, I use Postfix as my MTA, so my rules look like this:
reject_rhsbl_client malwaredomains.schulte.org, reject_rhsbl_reverse_client malwaredomains.schulte.org, reject_rhsbl_helo malwaredomains.schulte.org, reject_rhsbl_sender malwaredomains.schulte.org,Customize to your own needs.