RetroShare is a Open Source cross-platform, private and secure decentralised communication platform. It lets you to securely chat and share files with your friends and family, using a web-of-trust to authenticate peers and OpenSSL to encrypt all communication.

RetroShare provides filesharing, chat, messages, forums and channels.

RetroShare is the next generation sharing network, which provides a reliable Identification and Authentication of your friends, plus an Introduction Scheme which connects you to the friends of your friends, and facilitates network growth.

RetroShare features Encrypted Communication, ensuring all shared information is known only to you and your peers.
This Communication Platform can potentially support services such as Secure Email, File Sharing, Streaming, Video or Voice over IP, Photos, Wall and Messaging

Main Features:
Serverless, encrypted Chat & Filetransfer
Multiple simultaneous downloads / uploads
Search Friends
Messages
Forums
UPnP / NAT-PMP port forwarding support
GnuPG Authentication
OpenSSL Encryption
Plugins support
Graphical User Interface written with Qt4 toolkit
System tray integration

New in this version:
This release brings
revamped Channels and Forums
major improvements to File Transfer
Polished GUI design
much improved code stability.
a new DHT to help find your friends.
Many other improvements.