Bitcoiin is a cryptocurrency that was created to address some of the issues that have plagued the original Bitcoin ecosystem. It's Proof-of-Work (PoW) consensus mechanism is designed to decrease transactions times and fees, as well as make mining rewards easier to earn.

BlackCoin is a Proof-of-Stake (PoS) cryptocurrency created in 2014. Users are rewarded for staking their coins to secure the network. BlackCoin's staking rewards vary between 1% to 8% per year.

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.