I'm the developer of Skulls (a GWebCache).
In these months I have implemented numerous different ways for blocking spam hosts (and bad hosts) and also improving the bootstrap process.
It would be nice to know if there a some mods that are bad for the network and must be blocked.
I'm currently working beside other changes also to implement a way to distribute blocklists of bad ips directly from the web interface of GWebCaches using magnet links with also a fixed download source.
Most changes are already in the latest version (although not all yet).
You can see one online here:
http://disobscure.velum-ultra.com/skulls.php
I'm open to any suggestion for improving it.