You have a home server, could be home assistant, a Raspberry Pi, your desktop computer. Access that server and all services on your phone or laptop from anywhere without figuring out ports and worrying about your server being pwned. It all looks like local traffic.

Set the DNS server on your phone to a Pi running AdGuard Home and block all ads and trackers when on 5G, not just in the browser.

Travel abroad with your laptop and designate your computer at home as an exit node and now all the traffic on your laptop looks like it is coming from that country.

Those are just the use cases I am using personally.