Yeah, a public API anyone can sign up for, get a token, and call from anywhere to store key/value data, without needing to setup a server/database. Basically like Web Storage API, but saved in the cloud instead of locally, so that it persists.

I wasn't able to find anything that exists like this (if you know of any, please share). My interest is in using it, but if it doesn't exist, I wonder about building it as a service.