Namecoin is a blockchain-based DNS that allows users to register domain names with a ".bit" domain. Namecoin was the first fork of the Bitcoin protocol and it aims to remove centralized control over domain registration. It was the first cryptocurrency to use Auxiliary Proof of Work (AuxPoW) as a consensus mechanism,
where a child blockchain is dependent on the Proof-of-Work consensus of the parent blockchain. This allows for Namecoin and Bitcoin to be mined simultaneously, and when a new block is created on Bitcoin, it will also be added to the Namecoin blockchain.
Namecoin is a very important project that represents one of the best use cases of blockchain technology in protecting free speech and resisting censorship on the internet. It is powered by the NMC coin. The decentralized DNS provides more security from hackers and government intervention.

Hedera Hashgraph is a blockchain network that was designed to allow developers to create DApps that require higher throughput and faster settlement. Hedera uses its own consensus protocol that assigns every transaction a consensus time that is calculated as the median of the times at which each node in the network first received it. The network is powered by the HBAR coin.

Celer Network is developing a layer-2 scaling platform that aims to enable fast and secure off-chain transactions and off-chain smart contracts. The Celer Network hopes to enable developers to create scalable DApps by increasing the off-chain functionalities of blockchains.