For those who want a better security for their computer, this program is a privacy oriented firewall application. With PeerGuardian you can block any connections from other computers that are blocked and millions of IP’s with problems.
It can be used on Linux, on Windows and on OSX and it is very efficient.
If you want to download it, it’s good to know that is 100% free. Also, it’s an open project, so, if you want to contribute in any way, you can do it. For those who want more than this, PeerBlock is another program that comes with the same features and also with some more.