CCProxy - Want to share Internet connection? Get every computer online through a single Internet connection?
BlockParty - Real-time voice chat rooms from the creators of turntable.fm
Apache Traffic Server - Fast, scalable and extensible HTTP/S 2 and 1.1 compliant caching proxy server.
Block Together - A useful tool which helps you block trolls on Twitter.
3proxy - 3proxy freeware proxy server for Windows and Unix. HTTP, SOCKS, FTP, POP3
CleanSpeak - Keep inappropriate content and trolls out of your community