I've been thinking about a fun idea recently for small digital collectibles I'm calling virtual badges. Each badge is a tiny 64x64 pixel image that contains a cryptographically verifiable certificate of ownership embedded directly inside it. This isn't some NFT scam; there's no marketplace or blockchain in sight. They're completely non-transferrable, so it can never become that. It's more like little signed virtual trophies. With an open standard, anyone can mint a badge for anyone else, and anyone can verify that it was genuinely issued and genuinely accepted all without even needing an internet connection.
Here's the idea: users who own badges and mints that mint badges use a public key as their identity. A badge will contain structured info such as the minter's public key, the owner's public key, a timestamp, and a hash of the image. The minter signs this data with their private key, producing a cryptographic signature that says, "I affirm that I issued this badge to this user". Then the user signs as well, proving they accept it. The final certificate will be bundled into the image file in metadata so the file alone will contain the badge info, the minter's signature, and the owner's signature. Verification is just signature checking and recomputing the hash of the image. No network calls. No global registry. No blockchain. No centralized authority.
If they want, users and mints can optionally include information like a display name or url. For the purpose of making providing your public key easier as a user, I imagine one or more websites that might let you host your public key at a url with a simple to remember alias for convenience.
The goal is for collecting these to feel like a game of hunting and earning badges. I'm trying to finalize the first version of this open standard and then I'm going to create the first mint. Stay tuned for more.