Running cryptocurrency masternodes to produce smart passive revenue is another option to make money in the cryptosphere. A masternode is a cryptocurrency full node or computer wallet that, like Bitcoin full nodes, retains a full copy of the blockchain in real-time and is always up and running to perform particular duties.
Different bitcoin networks compensate masternode owners for completing such duties. However, in order to start running a masternode, you must have a certain number of coins. The minimum amount required to create a masternode varies every cryptocurrency, however it is often in the range of 1000 to 25000 coins.
Some proof of stake currencies that have the masternode functionality are:
See here for more proof-of-stake coins.