Soulseek!

RetroShare is a open source cross-platform, private and secure decentralized communication system. It lets you to securely chat, share photos, videos, and more, using OpenPGP to authenticate peers and OpenSSL to encrypt all communication.

SoulSeek is a p2p network/software, in particular geared towards finding music you may not find elsewhere, and finding about more music you may not know about!

MLDonkey is an open source, multi-protocol, peer-to-peer file sharing application that runs as a back-end server application on many platforms. It can be controlled through a user interface provided by one of many separate front-ends, including a Web interface, telnet interface and over a dozen native client programs.Its great when you have multple computers and you want to set up one server to download and in multiple computers with multiple users you can add files. (use it with Sancho Gui)

Simple and easy to useFully decentralized networkAll shared files are indexed locallyNo relaying of other user's searchesPure UDP protocol that utilizes forward error correctionFull connection encryption and decentralized public key infrastructureRecirculating token system that helps distribute upload bandwidth fairlyEfficient and fast transfers via re-combining and re-encoding blocks at all nodesClean install and uninstall, or stand-alone operation, with no annoying .Net or Java dependenciesNO Spyware NO Ads NO Nonsense »

Gigatribe is a p2p software with more than 1 Million users. Its an easy way to share and transfer files between friends or colleagues.

The Owner-Free Filing system has often been described as the first brightnet; A distributed system where no one breaks the law, so no one need hide in the dark.