Based, at least, in a CLI interface.

• airpaste – 1-1 network pipe that auto discovers other peers using mdns.
• blecat – 1-1 pipe over bluetooth low energy.
• deejay – Music player that broadcasts to everyone on the same network.
• dhtkv – CLI for storing arbitrary key/value data in the bittorrent mainline DHT.
• gun – A realtime, decentralized, offline-first, graph database engine.
• hyperpipe – Distributed input/output pipe.
• hypervision – P2P Television.
• instant.io – Streaming file transfer over WebTorrent.
• ipp-printer – Create a printer on your network.
• peercast – Like peerflix but for Chromecast.
• peerflix – Streaming torrent client.
• peervisionary – Stream p2p content over your local network.
• peerwiki – browse all of wikipedia using bittorrent.
• screencat – WebRTC screensharing app.
• signalhub – Simple signalling server that can be used to coordinate handshaking with webrtc or other fun stuff.
• torrent-mount – Mount a torrent (or magnet link) as a filesystem in real time using torrent-stream and fuse.
• webcat – pipe across the web using WebRTC.
• websocketd – Turn any program that uses stdin/stdout into a WebSocket server.
• webtorrent – BitTorrent over WebRTC.
• wifi-triangulate – Finds your current position on planet earth using the wifi access point.

Do one thing well.

• airplay-server – A low level AirPlay server.
• castnow – simple chromecast player.
• discovery-swarm – A network swarm that uses discovery-channel to find peers. Also check webrtc-swarm.
• dns-packet – Abstract-encoding compliant module for encoding / decoding DNS packets. Also see dns-socket.
• etcdjs – Low level etcd v2 client written in Javascript with failover support.
• geocode-wifi – Get yours latitude/longitude based on your wifi access point.
• hash-to-port – Hash a value to a valid port.
• hyperdb – Distributed scalable database.
• ip-packet – Encode/decode raw ip packets.
• magnet-uri – Parse a magnet URI and return an object of keys/values.
• mutex-server - Critical section controllers, like mutex and semaphore, in the network level.
• network-address – Get the local network address of your machine.
• network-simulator – Simulate a low-level computer network.
• rtsp-stream - A transport agnostic RTSP serial multiplexer module for Node.
• simple-peer – Simple WebRTC video/voice and data channels.
• simple-websocket – Simple, EventEmitter API for WebSockets.
• torrent-discovery – Discover BitTorrent and WebTorrent peers.
• torrent-stream – The low level streaming torrent engine that peerflix uses.
• udp-packet – Encode/decode raw udp packets.
• rpc-websockets - JSON-RPC 2.0 implementation over WebSockets for Node.js and JavaScript.

Implementation of protocols specs in pure javascript.

• airswarm – Network swarm that automagically discovers other peers on the network using multicast dns.
• bittorrent-dht – BitTorrent DHT protocol implementation.
• bittorrent-protocol – BitTorrent peer wire protocol implementation.
• bittorrent-tracker – BitTorrent tracker (client & server) implementation
• bonjour – A Bonjour/Zeroconf protocol implementation.
• castv2 – An implementation of the Chromecast CASTV2 protocol.
• dht-rpc – Make RPC calls over a Kademlia based DHT.
• dns-discovery – Discovery peers in a distributed system using regular dns and multicast dns.
• hypercore – A p2p network for distributing and replicating static feeds of binary data.
• ipfs – The InterPlanetary File System, a new peer-to-peer hypermedia protocol.
• k-bucket – Kademlia DHT K-bucket implementation as a binary tree.
• k-rpc – Implementation of the k-rpc protocol used the BitTorrent DHT. Also see k-rpc-socket.
• mdns – mdns/zeroconf/bonjour service discovery.
• multicast-dns – Low level multicast-dns implementation.
• peervision – Live p2p streaming protocol.
• polo – A zero configuration service discovery module.
• rtsp-server – A low level module for creating RTSP servers.
• utp-native – micro transport protocol, a network protocol similar to tcp that runs on top of udp.