Recently released Nosflare a serverless Nostr relay PoC purpose-built for Cloudflare Workers and the Cloudflare KV store.

This relay concept is designed to be easy to deploy, scalable, and cost-effective, leveraging Cloudflare's edge computing infrastructure.

So far, seems to be quite fast: https://nostr.watch/relay/nostr.coinfund.app

But lots of refinements and bugs to patch. Though, in current form it could be useful for having a free, small relay.

Check it out https://github.com/Spl0itable/nosflare