Idea for a geo-fenced Nostr Relay:

1. User enters in their mailing address to the relay sign up page
2. If address is within a certain city / area code range, the relay presents a payment screen
3. After payment is received, the service mails a physical access code to the user’s address (this could all be automated) 
4. User receives mail and enters access code on relay sign up page
5. Every year, the user renews access by following the same process again. 

This would work really well for smaller towns that don’t want to get brigaded by bigger cities.