Pull requests VERY welcome!

AnoNet is a decentralized friend-to-friend network built using VPNs and software BGP routers. anoNet works by making it difficult to learn the identities of others on the network allowing them to anonymously host IPv4 and IPv6 services)

BitMessage is a P2P communications protocol used to send encrypted messages to another person or to many subscribers. It is decentralized and trustless, meaning that you need-not inherently trust any entities like root certificate authorities. See whitepaper

Commotion Wireless is an open-source communication tool that uses mobile phones, computers, and other wireless devices to create decentralized mesh networks.

The Drogulus (WIP) is a programmable peer-to-peer data store. It's an open, federated and decentralised system where the identity of users and provenance of data is ensured by cryptographically signing digital assets.

eDonkey network is a decentralized, mostly server-based, peer-to-peer file sharing network best suited to share big files among users, and to provide long term availability of files

Freenet is free software which lets you anonymously share files, browse and publish "freesites" (web sites accessible only through Freenet) and chat on forums, without fear of censorship. Freenet is decentralised to make it less vulnerable to attack, and if used in "darknet" mode, where users only connect to their friends, is very difficult to detect.

GNUnet is GNU's framework for secure peer-to-peer networking that does not use any centralized or otherwise trusted services.

Grimwire is a browser OS which uses Web Workers for process isolation, and WebRTC for peer-to-peer communication.

Guifi is a european (especially spanish) large network with over 22000 active nodes. Uses wifi in both infrastructure and mesh mode. Over 25km of fiber as well so far.

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.

Kademlia is a distributed hash table for decentralized peer-to-peer computer networks

NameCoin is a decentralized naming system based on Bitcoin technology.

Nightweb connects your Android device or PC to an anonymous, peer-to-peer social network. You can write posts and share photos, and your followers will retrieve them using BitTorrent running over the I2P anonymous network. It is still experimental.

OpenNIC Project is an alternative DNS provider that is open and democratic.

Osiris is software for decentralized portal, managed and shared via P2P between members.

PeerCDN automatically serves a site's static resources (images, videos, and file downloads) over a peer-to-peer network made up of the visitors currently on the site.

PeerServer is a peer-to-peer client server using WebRTC, where your browser acts as a server for other browsers across WebRTC peer-to-peer data channels.

Project Meshnet aims to build a sustainable decentralized alternative internet. Used by Hyperboria and built on CJDNS.

Quick mesh project is an openwrt based mesh networking firmware. Can be installed on any openwrt supported system. Auto configures any needed connections, auto detects internet connections and aunounces them. Native IPv6 support with IPv4 tunnels for current networking support.

RetroShare is an open source, decentralised communication platform. It lets you chat and share with friends and family, with a web-of-trust to authenticate peers.

The Serval Project lets mobile phones make phone calls to each other peer-to-peer without a base station.

Syndie is an open source system for operating distributed forums offering a secure and consistent interface to various anonymous and non-anonymous content networks.

Tavern is a distributed, anonymous, unblockable network designed to ensure that no one is silenced, censored, or cut off from the rest of the world

Telehash a new encrypted P2P JSON-based protocol enabling developers to quickly build apps that are distributed and private (see v2 of the spec)

The FNF is the free network foundation: teaching how to build wireless community networks.

Tonika is a (digital) social network, which (by design) restricts direct communication to pairs of users who are friends, possesses many of the security properties (privacy, anonymity, deniability, resilience to denial-of-service attacks, etc.) that human sociaties implement organically in daily life.

Tox The goal of this project is to create a configuration free p2p skype replacement.

Unhosted - also known as "serverless", "client-side", or "static" web apps, unhosted web apps do not send your user data to their server. Either you connect your own server at runtime, or your data stays within the browser.

Vole is a web-based social network that you use in your browser, without a central server. It's built on the power of Bittorrent, Go and Ember.js. Uses bittorrent sync.

BitCoin is a digital currency, a protocol, and a software that enables it. Decentralized crypto-currency

LiteCoin is a peer-to-peer Internet currency that enables instant payments to anyone in the world (was based on Bitcoin)

I have moved most of the currencies to this section until I can determine there is an actual economy in existence around them and that they are not just forks/clones or what have you of the currencies above.

BBQCoin often abbreviated to BBQ or BQC is a scrypt based blockchain fork of the original bitcoin source code, very similar to litecoin and launched only a short while after Litecoin.

BitBar is a compilation of two projects by two groups: RareCoin project, and FairNova project [both abandoned]

Chncoin 基于Litecoin的新型货币 [A new coin based on Litecoin]

Devcoin is an ethically inspired project based on the BitCoin crypto-currency and created to help fund open source projects created by programmers, hardware developers, writers, musicians, painters, graphic artists and filmmakers.

Feathercoin is based on Litecoin, which is safeguarded from the effects of Bitcoin ASIC mining. It has a block reward of 200 coins and will have a total of 336 million coins. This makes it four times that of LiteCoin.

Frankos is a high-value decentralized Internet currency that enables anyone in the world to recieve instant payment for goods and services. Franko is based on the Litecoin protocol but differs from Litecoin in that it is 8x more rare.

Freicoin is a peer-to-peer (P2P) currency based on the accounting concept of a proof-of-work block chain used by Satoshi Nakamoto in the creation of Bitcoin. Unlike Bitcoin, Freicoin has a demurrage fee that ensures its circulation and bearers of the currency pay this fee automatically.

ixcoin is a peer-to-peer currency based on Bitcoin with a shorter maturity. Peer-to-peer means that no central authority issues new money or tracks transactions. These tasks are managed collectively by the network.

Junkcoin JunkCoin (JKC), the newest altcoin which is Litecoin-based has arrived!

MinCoin is a peer-to-peer cryptocurrency using scrypt as a proof-of-work algorithm.

MultiCoin is a branch of Bitcoin a crypto currency client with experimental and advanced features of multi currency and escrow and soon others [last activity 2 years ago]

Novacoin is a hybrid scrypt Proof-of-Work + Proof-of-Stake based cryptocurrency operating with no central authority via peer-to-peer open source network. Novacoin has no hard cap except for the 2 billion coin max that has been entered for coding purposes; this can be lifted in the future if needed.

PeerCoin/PPCoin is the first known cryptocurrency based on an implementation of a combined proof-of-stake/proof-of-work system

PhenixCoin was developed for use with our various sites. It is currently in use at our crypto coin based poker site PhenixPoker.com. We have a number of project currently under development and planned that will use Phenixcoin as their main currency.

RoyalCoin is a new scrypt based coin developed by 3 guys based out of Montreal

RuCoin Знакомьтесь: rucoin (RUC, рукоин, "рукошки", "руки") - крипто-валюта, пиринговая сеть с открытым исходным кодом, основанная на алгоритмах BitCoin.

[translation?] crypto-currency, peer-to-open-source-based algorithms BitCoin. Micro payments to support sites for free software developers, and for other beneficial endeavors - that is what RuCoin ideal.

Terracoin is a peer to peer decentralized currency based on Bitcoin. Terracoin has no central issuer; instead, the peer-to-peer network regulates Terracoin balances, transactions and issuance according to consensus in network software.

TimeKoin is a long tested form of encrypted digital currency that uses decentralized peer to peer networking to operate with no central controlling authority.

YACoin is the first Internet crypto currency to guarantee long-term protection against GPU and ASIC mining. This enables all peers to participate equally in the network, regardless of their financial backing. Whether you have a few Intel i7's or a ATI Radeon 5790 GPU, you can share in mining profitability.

Tidepools is being developed within the Red Hook Mesh Network, for addressing local, social incentives for mesh use. An Open Source, Collaborative, Mobile Mapping & Social Hub, Reflecting Community Needs & Culture through Custom Apps, Time-based Maps, & Data Feeds.