Tor - The Onion Router

It amazes me that onion sites aren't everywhere. They are easy to spin up, you don't have to pay anything and can run it from your own home. No need to purchase a domain, worry about expiration, have an open port. Built-in DoS protection. Anonymity and authentication by default. No need to configure HTTPS. Sure, uptime is on you and there is some latency/bandwidth limits to be considered, but once you are over that, onions are a solution to many problems and the benefits are enormous.