find niche

I'm looking to do some research for a new niche website. I've not decided the niche yet. I've got a giant list of niches to choose from and I'm looking to basically just find lots of different websites in each niche. What is the best way to find websites. Hopefully it's not as simple as...

Hello BHW members! I was just wondering, how do you guys find good/profitable niches for an (affiliate) site? Are there any tools you use to research the niche? I used to work with Google keyword planner to get some ideas and see competition, but how to narrow those niches down to some less...