I've always had an interest in chess. In fact I have over 10 websites related to chess. Two of which are earning me money via selling ad space and writing sponsored reviews.
This is funny because I've always had the opinion that chess will never bring any profit to me. In fact it's a hobby that requires some investments especially if you are serious about improving. You have to invest time and money to get quality books and coaching.
As for blogging for money, I've even been advised by popular gadget full time blogger LiewCF that chess is a niche that is NOT profitable. While what he said is true, my narrow niche also meant that my chess site is the top news website in Malaysia. The traffic is not high but daily visitors is consistently at 100 visitors and above for both of my chess blogs. This give me a regular income via Adsense and other advertisers. Also it was easier for me to become the leader in this niche than to become a leader in say technology and gadget topics as this has become too saturated with thousands of blogs talking about the same two topics.
In the end, it's chess that got me started in blogging for money. Of course I'll still listen to LiewCF advice and go into more profitable blog topics such as gadgets and technology since that is something I'm very interested in too. I'll experiment with new tourism related blogs since I'm getting a good hint of income from my Malaysian related blogs.