RetroShare is a feature-rich communications platform for small groups of users with a focus on privacy. The program includes an exclusive and secure toolset for instant messaging, chat rooms, forums, direct messages (e-mail), file server, VoIP, channels for distributing content and link exchange. It functions as an open, distributed alternative to many commercial groupware programs.

Additional features include RSS feed reader, status messages (away/busy), different modes for low traffic, transfer and disk space limits, plugins, skins and much more. Cross-platform (Mac, Linux, BSD).

Great for small businesses, groups, and a safer alternative to most file sharing methods. Networks can be small or large, but communications between users are limited by default to friends and friends-of-friends, with more specific controls available.