[nonameiguess]

Technically 25 years since Hashcash was first proposed. I'd argue it could have had value sticking to that original application in preventing network spam, but instead it turns out people are more interested in storing the proof-of-work tokens on a blockchain and selling them, as if collecting and trading postage stamps had become more widespread than actually sending mail with them, to the extent that at least some people and a few entire countries proposed replacing currency with postage stamps.