Cachechu
» This script acts as a GWebCache for gnutella 2 clients and is designed to have a light footprint on server resources.

CIPRG/Country Blocking
» Country IP Ranges Generator. As the name says, it can be used to generate the ipranges for a certain (or multiple) countries. It can be used for blocklists in PeerGuardian (and you can enter the url of the service, so the lists will be auto-updated). You can check out all of the features, or download the script here.