Get to know the business field you are interested in.
Show the typical cost structures of businesses in different fields, and case studies of failed and successful companies and why they failed or succeed.
You are planning on taking an active vacation by visiting a foreign city and touring its sights. How much will it cost per day?
An app that lets you choose a city, the activity level (how many museums, sites, etc. you would like to visit per day), eating habits (how many hot meals, etc.), and where will you stay (to calculate travel expenses), and gives you a from-to list of expense possibilities for each item.
See how much it costs to make what you buy.
Publish studies on well know products, showing their price structure, how mich it costs to develop, manufacture, market, etc.
It might lead to more income and better relationship with the customers.
Show cost of the online information product (making and marketing), how many you need to sell to make a profit, and how many already sold. Emphasize the smaller amount (first the amount sold, when the amount needed to turn a profit is near then show the amount still needed, and when the profit exists then show the profit.)