If you're talking about the "deep web" as in tor, i2p, etc, you won't be impressed. It's literally nothing but cp, drugs, and scams, which makes since, because if it could be hosted in the "clearweb," then why would anyone want to host it in the deep web. The reason why the "deep web" is so large is because everything that isn't on google, such as private messages on this website is considered "deep web." There's nothing special really.