Ah yes, the Chaum paper. The "Hey here is a cool thing you could do and solve a billion problems. Oh by the way we've patented the shit out of it and our royalt

Ah yes, the Chaum paper. The "Hey here is a cool thing you could do and solve a billion problems. Oh by the way we've patented the shit out of it and our royalty rates are pretty extreme. Ha ha ha!" I think the last of the patents expire in 2023 which allow for an end to end zero knowledge based local transaction ledger system. That will be useful.