Ravencoin is a blockchain created by the owner of Overstock.com. It is a use case specific blockchain for the declaration of ownership of digital assets. Ravecoin is a fork of Bitcoin, and was originally funded by Medici Ventures, a blockchain investment fund owned by Overstock.com.
Ravencoin's name is inspired by the use of Ravens in sending messages, and its blockchain is designed to carry statements of truth about who owns what asset. The developers created a new consensus algorithm called x16r to solve the problems of centralized ASIC mining. The algorithm is unique in that it consists of 16 different hashing algorithms whose order are randomly changed.

Digix is digital gold on the blockchain. By combining the historical stability of a valuable physical asset with the advantages of a distributed ledger, Digix allows users to benefit from the advantages of both commodities and digital tokens.
Digix has an innovative Proof of Asset (PoA) protocol that allows it it tokenize a physical asset. The PoA protocol tracks an asset through its chain of custody, and enables anyone to verify its existence without an intermediary. Since every DGX = 1 Gram of gold, their platform can be used as a secure and transparent digital marketplace for gold.
Digix is also behind DigixDAO, a platform that allows users to contribute to building a blockchain-based digital gold payment system. They hope to create a decentralized autonomous organization (DAO) that will participate in creating this platform. Instead of issuing shares, the organization will be run by DigixDAO token holders.