Primecoin is a cryptocurrency based on finding prime numbers. Identifying prime numbers plays a central role in cryptography. Primecoin's unique Proof-of-Work (PoW) consensus mechanism is able to increase transaction speeds and improve energy efficiency.
The network searches for special prime number chains known as Cunningham chains and bi-twin chains, which are of interest in mathematical research.

Lightning Bitcoin is a cryptocurrency protocol with a DPoS consensus mechanism. It is a hard fork of Bitcoin that was created with the goal of improving transaction speeds and scalabilty. Lightning Bitcoin's on-chain governance system enables LBTC holders to vote for the blockchain improvement proposals and the delegates who maintain the network as Lightning Nodes. Lightning Bitcoin is not related to the Lighting Network, which is an off-chain protocol built on the Bitcoin blockchain.

Divi is a Proof of Stake cryptocurrency with a masternode system designed to encourage network participation. The project is focused on facilitating adoption of cryptocurrencies by creating a system of incentives for both everyday users and those that help run the networks. Divi's masternode system has five layers of participation and awards users for staking their coins. Divi has an innovative lottery block system that randomly pays out lottery prizes in the form of new coins to network users.