OneSwarm!

The qBittorrent project aims to provide a Free Software alternative to µtorrent. Additionally, qBittorrent runs and provides the same features on all major platforms (Linux, Mac OS X, Windows, OS/2, FreeBSD).

µTorrent is a lightweight BitTorrent client that includes standard features such as bandwidth prioritization, scheduling, RSS auto-downloading and Mainline DHT. Additionally, µTorrent supports the Protocol Encryption joint specification and peer exchange.

Deluge is a full-featured BitTorrent client for Linux, Unix and Windows. It is written in python, uses libtorrent (rasterbar) at its core and GTK for the main user interface along with web and console interfaces for advanced client/server facility.

I2P is an anonymizing network, offering a simple layer that identity-sensitive applications can use to securely communicate. All data is wrapped with several layers of encryption, and the network is both distributed and dynamic, with no trusted parties.

Tixati is a peer-to-peer file sharing program that uses the popular BitTorrent protocol. This protocol allows many peers to form a cooperative swarm and download very large files with great efficiency.

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.

TunnelBear is a fancy new app for Windows and Mac that lets you “tunnel” your Internet connection through their US and UK server. It functions very much the same as VPN that let’s you access US and UK restricted website such as Hulu and Pandora. Since your internet connection is encrypted and tunneled, it is also possible to use TunnelBear to bypass blocked website easily and effortlessly.

Tribler is an application that enables its users to find, enjoy and share content. With content we mean video, audio, pictures, and much more. Tribler has three goals in helping you, the user: find, consume and share content.

Using WebRTC, FilePizza eliminates the initial upload step required by other web-based file sharing services. When senders initialize a transfer, they receive a "tempalink" they can distribute to recipients. Upon visiting this link, recipients' browsers connect directly to the sender’s browser and may begin downloading the selected file. Because data is never stored in an intermediary server, the transfer is fast, private, and secure.

rtorrent is a BitTorrent client for ncurses, using the libtorrent library. The client and library is written in C++ with emphasis on speed and efficiency, while delivering equivalent features to those found in GUI based clients in an ncurses client.

FrostWire is a free, open source P2P BitTorrent file sharing application & cloud file downloader in one. It's a fork of LimeWire .