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.

DigiByte is a a blockchain platform that places an emphasis on security and block speed. DigiByte has one of the fastest block speeds of any public blockchain and uses an innovative consensus protocol with 5 mining algorithms. This prevents mining centralization and also minimizes the chances of security breaches. DigiByte transactions are limited in size and scope to increase speed, efficiency, and throughput.
DigiByte hopes that these innovations will provide the ideal blockchain infrastructure for a range of applications within the IoT and AI fields, that require a high degree of security and fast block speeds.

PIRL is a community based blockchain project focused on making cryptocurrencies more accessible. It was the first blockchain to introduce an Ethash-based masternode. Their goal is to develop a comprehensive DApps hosting infrastructure that will be easy to use. Their Poseidon platform is designed to be an on ramp for users without any technical knowledge. PIRL's multi-tiered masternode network has an ASIC-resistant Proof-of-Work (PoW) consensus mechanism, and is powered by the PIRL coin. The company plans on developing features, such as: decentralized file storage, messaging, and escrow services for payments.