If you are thinking about blogging and looking for a profitable niche, you can try blogging on cryptocurrency. Check Google trends, or Google Keyword Planner tool, you'll see cryptocurrency is one of the most searched topics on search engines. But keep in mind, this area is really crowded. When a niche is crowded, it means there is a huge competition, which makes harder for your blog to show up high in search results. If you cannot get on the first few pages of search results, you won't get much traffic and without traffic, making money is near to impossible. Likewise, you will also have to compete with big websites that are using this niche, it is tough to compete with them.