Boolberry is a cryptocurrency based on CryptoNote technology. Boolberry's major benefit is to provide much stronger privacy to both the senders and receivers of transactions. The destination of a transaction can only be determined by its real recipient and transactions cannot be linked to a single sender. Each transaction could have many equally possible senders, and an attacker cannot determine which one it was. There is an aliasing facility built into the blockchain so that people or programs can send money to, for example, '@zoidberg' instead of a long address.
Novacoin is a hybrid Proof of work (POW) / Proof of stake (POS) decentralized peer-to-peer cryptocurrency.The Proof of Work part of Novacoin is based on the Scrypt hashing algorithm. Proof of Stake contributes to the coins energy efficiency, as there is no need for nodes to contribute mining power to part of the money creation process. As of now, Novacoin is set to be capped at 2 billion coins. However Novacoin stated that the cap limit may be lifted if the situation requires it. It looks very much like a variation of Sunny King Peercoin.