BitComet is a BitTorrent/HTTP/FTP download management software, which is powerful, fast, very easy-to-use, and completely FREE. The advanced features it contains can accelerate your downloading speed up to 5 - 10 times faster, or even more. Native support for 64-bit system.
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. Once the Tixati software is installed, starting a download is easy.
Shareaza™ is the most luxurious and sophisticated file sharing system you'll find. It can harness the power of up to four separate peer-to-peer (P2P) networks, including EDonkey2000, Gnutella, BitTorrent and Shareaza™'s native network, Gnutella2 (G2).
The Vuze Bittorrent Client is an end-to-end application for all your torrent needs. Although it is a complete bittorrent downloader, Vuze maintains a lightweight footprint, doesn't slow your computer down, and quickly downloads torrents. Vuze makes it easy for you to find torrents anywhere, whether you are downloading torrents from a tracker site or anywhere else on the web.
Halite (named after the mineral) is a C++ BitTorrent client based on the excellent libtorrent library from Rasterbar Software. The program also relies on the Boost libraries and in the future on my own libHTTP for the still to be implemented remote control interface from Java enabled (MIDP 1.0) mobile phones.
Qt based GUI tool designed to create and edit .torrent files
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This is a portable bittorrent client with basic features along with support for extensions. It is currently being actively developed on Windows 7, Debian and OSX 10.6.8. The most recent releases (9-dec-2012) are 0.2.2 for Windows 7, Debian 6.0.6 and Ubuntu 12.04, all 64-bit. I am not planning 32-bit releases for at least the next week. OSX will be released in a few days.
Utorrent has released a 64 bit build for Linux platforms (see details here). The release is built on Ubuntu 12.04 (LTS). The problem is that if you try to run it on a distribution like RHEL/CentOS or any older distribution with old libraries, it will fail because of the newer dependencies like glibc 2.14 and libssl 1.0.0 etc.
PeerProject is a versatile peer-to-peer file sharing client and file manager. It is intuitive and aesthetic while supporting many networks and features. Currently it supports BitTorrent, G2, Gnutella, eDonkey, DC++, IRC, and http/ftp. It is small and lightweight and combines both torrent and peer-2-peer file downloads at the same time. It searches torrents and P2P networks - ISO Hunt, Gnutella, eDonkey.
New version! - µTorrent is a BitTorrent client originally created by Ludvig Strigeus (ludde), and is currently maintained by a team of developers at BitTorrent, Inc. A client is a computer program that follows the rules of a protocol. For example, HTTP (HyperText Transfer Protocol) is the protocol used for transferring web pages and other content, and your HTTP client (or web browser) is the program you use to get those web pages.