Real estate is the obvious choice if you are going to make money on your money. I personally am not at the point where I can do any of this in a meaningful way BUT my parents are and they now own a couple homes outright and are collecting income from them to power their retirement income. It makes a lot more sense for anyone that has a chunk of cash sitting in the bank and are planning on slowly drawing from it because you technically still have all that money in a property (or multiple properties) and can sell them if you really need the lump sum of cash but you’ll earn great interest payments until you do that.
The second form of residual income, passive income, is often a vital part of wealth creation. There are only so many hours in each day, and when a person trades hours for dollars, there is a maximum amount of income that person can earn. For instance, if a person earns a specific amount each hour, there is a limit to how many hours are available to work. Once they reach that maximum amount of time, they cannot earn more money.
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.