This is an old vid from the late 70's on food processing and self-reliance from Kurt Saxon, father of prepping. It shows how to sprout grains and seeds, dehydrate them with a homebuilt food dryer (made from a cardboard box, tinfoil, wire mesh, and a plugged in lightbulb) then grind them into flour for bread.
He also goes into making an autoinjector for poisons, and a detonator made of pvc pipe, match-heads, endcaps, twine and superglue.
I've never seen any of this stuff anywhere on any chan, sure the four winds shotgun, but never anything else of it.