As Coin_trader already mentioned, e-commerce is still developing and I can assume that it will become more and more popular in the future. You could look for a niche product or service related to cryptocurrency or blockchain technology that isn't already well-served online.

Another service with future potential is a customer-centric crypto payment processor. Unlike traditional processors for merchants, this would allow customers to shop at any online store and pay with cryptocurrencies, acting as an intermediary between buyers and merchants. I know this idea requires a lot more than just web hosting and a domain, but it might be worth thinking about.