Horizen, formerly called ZenCash, is a cryptocurrency focused on privacy. Horizen has an end-to-end-encryption system with zero-knowledge technology, that allows for anonymous transactions and messaging.
The company suffered a 51% attack in June, 2018 and has since re-branded as Horizen. Horizen hopes to combine anonymous transactions and messaging with an emphasis on community governance.

Boolberry is a Proof-of-Work privacy coin designed to enable completely anonymous financial transactions. Boolberry's architecture reduces block size to improve transactions times, and has a mining algorithm that is ASIC resistant.

Bitcoin Private is a community-driven fork of the Bitcoin protocol. It is somewhat unique in that it was created as a result of a privacy-focused co-fork of Bitcoin and ZClassic. Coins were distributed on a 1:1 basis to BTC and ZCL holders. Bitcoin Private (BTCP) uses the same privacy technology as ZClassic (zk-snarks). Transactions are published on a public blockchain, but the sender, recipient and other transactional metadata remain anonymous. Bitcoin Private has a larger block size, and enables anonymous transactions that are more secure than the original Bitcoin protocol.