PeerGuardian is a free open-source application that helps protect a user's privacy while downloading or sharing files on the internet. It has the ability to block communication from known malicious IP addresses that have been identified as potential threats. PeerGuardian also allows users to create custom lists of IP addresses to block. The application works by creating a virtual firewall that filters incoming and outgoing connections, allowing only those that are safe and secure. It is available for both Windows and Mac OS X operating systems.
Discontinued The official website is no longer available. The latest version, 4.4, released in September 2011, can still be downloaded from MajorGeeks.
Discontinued The project is no longer being developed. The latest version, 0.29, released in October 2010, can still be downloaded from the official website.
PeerBlock
simplewall
CacheGuard-OS
BeeThink IP Blocker
HostsXpert
iplist
Discontinued The project seems to be no longer developed. The latest version, 1.2, released in January 2014, can still be downloaded from the official website.