To earn money, you may need to take some risks or experiment a bit. In this world of Internet, you can easily try to do different things and experiments to make money. In the below mentioned link, I'll show you one simple experiment that I am doing to make money. This experiment is nothing but the usage of one keyword phrase 'Experiment to make money' to appear on first page of Search Engines on different keywords.
If this experiment gets successful, it can fetch me some dollars from Google AdSense and will help me in trying different experiments to make money.