Adsuck is a small DNS server that spoofs blacklisted addresses and forwards all other queries. The idea is to be able to prevent connections to undesirable sites such as ad servers, crawlers, etc. It can be used locally, for the road warrior, or on the network perimeter in order to protect local machines from malicious sites.
You can download it from the following link: https://packetstormsecurity.com/files/download/109748/adsuck-2.4.2.tgz
Source: https://packetstormsecurity.com/files/109748/AdSuck-DNS-Server-2.4.2.html