There are such places where you can spread unscientific nonsense over gullible flocks.
They are usually named "churches", "temples", "synagogues", etc.
"that probably requires cryptography, hence computing power, hence money"
Cryptography is useful only when you need to be able to restore the data.
Assuming they don't need/want to restore the data. it is trivial to make a perfectly irreversible one way function
like a constant function (which is suitable if the area is small). or colour average on absolute coordinates.
Slashdot Mirror
There are such places where you can spread unscientific nonsense over gullible flocks. They are usually named "churches", "temples", "synagogues", etc.
mmmhhh Chocolate Boobies...
"that probably requires cryptography, hence computing power, hence money" Cryptography is useful only when you need to be able to restore the data. Assuming they don't need/want to restore the data. it is trivial to make a perfectly irreversible one way function like a constant function (which is suitable if the area is small). or colour average on absolute coordinates.