IPFS is a global, versioned, peer-to-peer filesystem. It combines good ideas from Git, BitTorrent, Kademlia, SFS, and the web. It is like a single bittorrent swarm, exchanging git objects. IPFS provides an interface as simple as the HTTP web, but with permanence built in.
Zero Install is a decentralised cross-distribution software installation system. Other features include full support for shared libraries, sharing between users, and integration with native platform package managers.
DASH is an open source peer-to-peer cryptocurrency that uses a system called Darksend to add privacy to transactions. It allows you keep your finances private as you make transactions, similar to cash.