Application of P2P network outside computer science

Bioinformatics: P2P networks have also begun to attract attention from scientists in other disciplines, especially those that deal with large datasets such as bioinformatics. P2P networks can be used to run large programs designed to carry out tests to identify drug candidates. The first such program was begun in 2001 the Centre for Computational Drug Discovery at Oxford University in cooperation with the National Foundation for Cancer Research. There are now several similar programs running under the auspices of the United Devices Cancer Research Project. On a smaller scale, a self-administered program for computational biologists to run and compare various bioinformatics software is available from Chinook. Tranche is an open-source set of software tools for setting up and administrating a decentralized network. It was developed to solve the bioinformatics data sharing problem in a secure and scalable fashion.
Academic Search engine: The sciencenet P2P search engine provides a free and open search engine for scientific knowledge. sciencenet is based on yacy technology. Universities / research institutes can download the free java software and contribute with their own peer(s) to the global network. Liebel-Lab @ Karlsruhe institute of technology KIT.
Education and Academia: Due to the fast distribution and large storage space features, many organizations are trying to apply P2P networks for educational and academic purposes. For instance, Pennsylvania State University, MIT and Simon Fraser University are carrying on a project called LionShare designed for facilitating file sharing among educational institutions globally.
Military: The U.S. Department of Defense has already started research on P2P networks as part of its modern network warfare strategy. In November, 2001, Colonel Robert Wardell from the Pentagon told a group of P2P software engineers at a tech conference in Washington, DC: "You have to empower the fringes if you are going to... be able to make decisions faster than the bad guy".[8] Wardell indicated he was looking for P2P experts to join his engineering effort. In May, 2003 Dr. Tether. Director of Defense Advanced Research Project Agency testified that U.S. Military is using P2P networks. Due to security reasons, details are kept classified.
Business: P2P networks have already been used in business areas, but it is still in the beginning stages. Currently, Kato et al’s studies indicate over 200 companies with approximately $400 million USD are investing in P2P network. Besides File Sharing, companies are also interested in Distributing Computing, Content Distribution, e-marketplace, Distributed Search engines, Groupware and Office Automation via P2P networks. There are several reasons why companies prefer P2P sometimes, such as: Real-time collaboration--a server cannot scale well with increasing volume of content; a process which requires strong computing power; a process which needs high-speed communications, etc. At the same time, P2P is not fully used as it still faces a lot of security issues.
TV: Quite a few applications available to delivery TV content over a P2P network (P2PTV)
Telecommunication: Nowadays, people are not just satisfied with “can hear a person from another side of the earth”, instead, the demands of clearer voice in real-time are increasing globally. Just like the TV network, there are already cables in place, and it's not very likely for companies to change all the cables. Many of them turn to use the internet, more specifically P2P networks. For instance, Skype, one of the most widely used internet phone applications is using P2P technology. Furthermore, many research organizations are trying to apply P2P networks to cellular networks.