[AJTSheppard]

Truth be told, that is exactly how I used to generate my crypto keys.

I would take 256 quarters (sometimes fewer and accept that some might be tossed more than once) and toss them to get ones and zeroes. Tedious, and somewhat error prone (see below). Then do the calculations by hand, also somewhat tedious and error prone.

There is plenty of research that demonstrates that humans are poor at tossing coins in an unbiased way. People cheat (especially if money hangs on the outcome) and people are also lazy, so that the first toss is vigorous and diligent, and so the coin tumbles end-over-end many times before coming to rest for a result (heads or tails), but after several hundred tosses, the vigor and diligence are gone and the coin barely leaves their hand.

Part of my motivation in building the Satoshi9000 was to automate this manual process and at the same time take out human bias. Which is to say, automate away the human part and automate the math of key generation. But at the same time, make it secure by having the machine air-gapped (that is, no connection to the outside world beyond a power cord) with the ability to walk-away with anything that might leave a clue as to how, why and when the machine was last used; what I refer to as "walk-away randomness" in the video. After removing the coins, SD cards (OS and user programs) and printout, what is left is little more than a motor and some wires. An adversary looking to recover your keys would have no clue as to whether the machine had ever been used, yet alone what for. Maybe it was simply used to generate a quick-pick for tomorrow's drawing of Powerball. You would have now way of knowing.

(As an aside, you could even walk away with the remaining paper roll from the printer, so an adversary would not even know how much had been printed! Also, the printer uses no ink and has no buffer/memory, which was a deliberate choice in the design.)