1 sat \ 0 replies \ @nullama 8 May 2023 \ on: Dumb idea: offline, no third party bitcoin coins bitcoin
That's literally what the first ever physical Bitcoin coins, Casascius, were.
You can move them around and whoever holds them has the private keys.
You can scan the address with your phone and verify the amount is still there.
There are many other projects that work like this as well, plenty use lightning as well for smaller amounts.