Thanks to PoS (Proof-of-Stake), it is possible to earn not only from a trade but also just from the possession of cryptocurrency.
The most interesting cryptocurrencies for passive income:
NEO and its related coin GAS. It is necessary to consider that not all purses are identical therefore it is important to check in advance whether the chosen purse allows earning rewards in GAS. Annual profitability makes 4−6%.
Dash. Profit is rather high about 7,5−8,4%. Minus is that creation of a master node requires not less than 1000 coins - about $162 thousand.
PIVX. Creation of a master node requires 10 thousand PIVX for the total amount about 12 thousand dollars. Profitability about 5,5% a year.
They are not near what you would consider proper for a staking, don't mistake just because you have your money staying there doesn't mean you are profiting. Even a 50% annual pay would mean nothing if the coin drops 50%. People who have invested into dash last year did not made any profits at all this whole year because the price has fallen. Even a 4% interest would have made more money for you because your money wouldn't lose value in a bank.
Hence if you want to get into staking or masternode work than you need to make sure the price of the coin you invest into would go up or at least stay the same price for a foreseeable future (at least until you get out). Dash was 1.5k at its peak, right now it is 156 dollars, thats 1/10 of what it used to be, you can have as much interest as you want and thats still an insane drop in price.