I have a need in a project I'm doing to be able to discover Tor onion services responding to a common hash. BitTorrent DHT libs were too inflexible for my needs. I was able to get this to work successfully with libp2p's DHT and my Tor controller lib. There are obviously several applications of this, it's basically just https://github.com/OpenBazaar/go-onion-transport and simple DHT logic.
See the code here. Feedback welcome/appreciated.