Use Online Forums to find a hot market. Forums or Discussion Board is where people show their problems and needing solutions. Affiliates have been successful marketing their products in Forums. You can spot many potential money making niches in Forums by finding using this method.
When you head over to Forums, find out the post thread that is active with replies and that has large number of views. Research on the post topic, develop a product and sell it back. Let me explain with this example. You come across a post with the topic "How can I get my ex-girlfriend back"? That's a hot topic which will bring in many answers offering solutions to the topic. How do you turn this particular post into profit? Here are Two tips.
1. Research on the topic and compile a list of solutions on How He can get his ex-girl back. Bundle your findings in an e-book. Write a short article that pre-sells your e-book, for example "How to get your ex-girl back in 5 simple Steps". Then head over to that same forum and post it. What you've just done is giving out tips that will lead your readers to find out more which will be in your e-book. Leave a link to your sales page where the e-book can be bought and downloaded.
2. The second way is to sell Affiliate Products on the same topic. It follows the same pattern where you just need to post a pre-sell article that guides your readers to check out more through your Affiliate link to the sales page.
You will earn money in both ways depending on any method you use. The underlying fact here is to spot what people are looking for or what they need, produce the solution in an e-book, software, e-course, or report format and sell it back to them.
The way you can make even more money is to repeat the process and spread across different niches you discover. This is the proven way you can discover your own money making niche and line your bank account with profits.