There are many people who want to run their own business but do not have all the skills/money required to start and grow the business. Some have 101 Nigerian business ideas but do not have all the people required to execute them;

82. Tech/Healthcare: One of the most annoying things about going to a hospital is having to wait for a long time to see a doctor and/or being told that the doctor you want to see is not available. How about creating a platform that enables patients to see the schedule of their doctors and book their appointments.

72. Dating site: Many young Nigerians are not strangers to continual pressure from parents to get married. While people in the West have not been subject to this kind of pressure, they have been able to create dating platforms that make it easier to meet people.

54. Food/Confectionery: The last time I checked, Nigeria was still a producer of Cocoa. Cocoa is the main ingredient for chocolate. We should start producing our own chocolates rich in cocoa and stop patronizing these big international brands that do not produce authentic quality chocolate. 

44. Tech/Events: Many Nigerian wedding invitations are designed for physical printing; after the event the card is tossed in the bin. Physical prints aren't the only option. A platform can be created that allows the couple to design their own wedding e-invitation card

36. Education: The days are long gone when the only place a person can learn is in the confines of a physical classroom. There are many online educational channels where people can learn all manner of subjects. You can own your own online school and avoid all the administrative, regulatory and financial requirements that come with opening a physical educational establishment.

...This is where the solution comes in an online directory for handy technical works. where this is different from yellow pages directory is the customer review/evaluation part...

Entrepreneurship is all about providing solutions that make people's life's a little easier. Who says you can't have money off simple ideas?