SIBCoin is a Proof-of-Work coin that was originally based on the same code as the Dash blockchain. SIBcoin was developed by a team of cryptocurrency enthusiasts in Siberia and it has gained a significant following in Russia.

MonaCoin is the first alternative cryptocurrency developed in Japan. It is based on the popular Japanese character, Mona. MonaCoin has a Proof-of-Work (PoW) consensus mechanism and uses a version of the Lyra2RE mining algorithm that was first used by Vertcoin.
MonaCoin has an enthusiastic user base that has developed a variety of Mona-based web applications and services. MonaCoin holders also use the coin as a tipping system.

BitcoinDark is a fork of Bitcoin with a poorly defined purpose and use case. BitcoinDark is based on the InstantDEX protocol, a decentralized exchange for BitcoinDark and other cryptocurrencies supported by the project. The platform is also supposed to include a Pegged Asset Exchange (PAX) to allow users to buy and sell pegged assets – including fiat currencies, commodities, ETFs, and stocks.
BitcoinDark is a Proof-of-Stake (PoS) currency that has gained a significant market cap, but the project has failed to show how its vision will be implemented or how it will add value compared to other blockchain projects.