Proof-of-Work Backed Tokens

Ergo allows the issuance of one token per transaction, where the token id must match the id of the box of the first input.

When a box is generated, the id of the future token is known. This id is computed through hashing.

By iterating over a register (for example, R4) used as a nonce, a token with specific id properties can be created. This could include ids starting with a certain number of zeroes. Therefore, some computational work may be required to generate such a token, similar to the VanityGen-address concept in Bitcoin, but applied to tokens.

Certain contracts may only accept these Proof-of-Work backed Non-Fungible Tokens (NFTs).

While specific use-cases have not been fully explored, potential applications could include spam filtering.

For more detailed discussions, refer to this link.