There are projects like Phonon from GridPlus which use industry standard hardware to enable secure, private, offline trading of units of crypto. This is effecti

There are projects like Phonon from GridPlus which use industry standard hardware to enable secure, private, offline trading of units of crypto. This is effectively digital cash. https://docs.phonon.org/readme https://docs.phonon.org/readme There's also https://kong.cash/ https://kong.cash/ and others. The need for untraceable and physically usable money is a top priority for cypherpunks and we are doing pretty well on that front.