The Circle 0.41c

The Circle is an open source scalable decentralized peer to peer application. What does that mean? Well, theres no central authority running the show. No entry taxes either, no censorship, and (in theory) no weak point which can break the whole system.
No one even owns the source code. As long as there is one Circle peer running, anywhere in the world, theres still a network.
Main features:
- Share files
- Send instant messages and chat IRC-style
- Put together your own personalized, trust based news service
- Proxy Debian package downloads
The Circle is written in Python. It runs on Linux and Windows. (in fact, there is very little operating system specific code, so it will most likely work on any system that supports Python)
Scalability
At the core of the Circle is a decentralized hashtable, or "Chord". This table allows users to search for files in logarithmic time, based on keywords. This means that the Circle does not have the scalability problems of Gnutella style network (such as Kazaa, eDonkey), while also avoiding the need for a central server and therefore a single point of failure. Details of its operation are given in the "Technical Details" section below.
Privacy
The Circle does have the ability to post fully anonymous news a la Freenet. However, the file-sharing protocol isnt entirely anonymous. People will be able to work out your IP address.
In order to protect user privacy, the Circle includes a Digital Rights Management system. Although everybody can search your files by their keywords, you may choose which users are authorized to download them. An unauthorized third party has access only to the names of your files, not to their content. Needless to say, we expect you to use this system in order to prevent copyright infringement, while allowing private copy.
Note: If we become aware that you are trying to share snuff or child pornography, we will be able to work out your IP and from that your location and identity, and report you to the police and/or your ISP. Snuff and child pornography are things we think any reasonable person considers to be evil (its an issue quite separate from the debate over copyright).