A portable, modular and efficient ftp server, supporting SSL, IPv6, UTF-8 compliant, multithreaded, modules ,externals scripts. unix-like permissions+acls, virtual users/groups, security, speed, bandwith limitation (user,group,global), group admins, per
OpenHerald is a free P2P software package with privacy and security as top priorities. Online messenger, File sharing, Chat, Newsgroups and more!
Unworkable is a BitTorrent implementation written in C using libevent. Goals include high code quality, efficiency, simplicity and security.
hotwired is a Hotline server for Unix-like operating systems. It aims to implement all the features of the level 2 Hotline protocol (i.e. Hotline > 1.5), including transfer queues, threaded news, and user management.