Almost a few days ago, I earned $ 15 out of the blue and at the same time did not use a single coin from my wallet. On the Nominex exchange, I received a bonus $ 50, which is given to the user for trading, but only the amount that you received as a result of trading with this bonus is credited to the main balance, and the $ 50 is valid only for 7 days. I just managed to buy Bitcoin for $ 50 and two days later, when Bitcoin reached 24K, I already had $ 65 on my account. 50 dollars burned out after 7 days, and 15 dollars remained on my balance.