Any good business ideas for a 17 year old?

Any good business ideas for a 17 year old? I have invested money in mutual funds but it is not enough. I want a business to earn more. If you have ideas, please do give me some. What good business with small capital? I am interested in those making programs for companies and also web development and Mobile Development applications. If you have ideas, please do post here. Maybe I should look for partner that will look over business while I am going to school? I want to be like Gates in the future or Trump.
How do you market something like a newly created program via visual basic? Or any other computer programming language? How do you market it to big companies that will buy the program?
I need programmers. And if I FOUND PROGRAMMERS and made a program, how would I market it then?

You could try reading some business books. Since your idols are Gates and Trump you could start by reading some of the books written by them or about them. Good luck.

Mobile Application Development