When researching niche profitability in affiliate marketing, you might want to start with tools like Google Keyword Planner to see search volume and competition. Another useful tool is Ahrefs, which can give insights into the traffic and backlinks of potential competitors. Also, consider using Amazon's Best Sellers list to gauge product demand. These tools can help you understand if a niche is worth pursuing. It's good to combine data from multiple sources for a complete picture. What do you think about these tools? Do you have any other suggestions or experiences to share on researching niche profitability?