Decred (DCR) is a decentralized currency with an emphasis on community based governance. Decred is led by several early adopters of Bitcoin and is designed to implement many of the goals of early Bitcoin idealists. Decred is highly focused on community contribution and governance. Users that contribute to the community can receive compensation for their work and anybody can submit a proposal ti make an improvement to the platform.
Decred has a hybrid Proof-of-Activity (PAC) consensus algorithm that combines the mining of Proof-of-Work (PoW) with the stake verifying model of Proof-of-Stake (PoS). It's designed to incentivize the community to participate and to reward both miners and stake verifiers. When DCR is mined, PoW miners receives 60% of the coins, PoS voters receive 30%, and 10% goes towards the development of the Decred platform.

.

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.

ILCoin is a PoW cryptocurrency. Their goal is to become the first cryptocurrency that uses the SHA-256 encryption algorithm to be able to execute smart contracts. The ILCoin is traded on several exchanges under the symbol ILC.