Not all information is equal in achieving useful work, nor is it straightforward to separate weeds from crops. Three empirical examples illustrate this point. The Atlas of Economic Complexity; the relation between economic development and different scientific activity in a country; and measuring learning in digital games. The first example shows that complexity and information underlying different industries have different effects on the economic development of a country. The second example shows that the development of different scientific fields has different impacts on the economic development of a nation. The third example shows that the way you present information affects acquisition of information. Thus, Useful Information differs in form, in complexity, and its effects on Useful Energy. Unfortunately, no magic master equation is available to calculate Useful Information. Only empirical, experimental, studies will throw more light on these issues.