Woodland winter fungi…
Hoof Fungus (Fomes fomentarius) can be used as tinder for lighting fires and apparently can be hammered flat into something like felt which will smoulder and so could be used to transfer fire from place to place before matches were invented.
Honey fungus, of which there are a few different species in the UK of varying ability to kill trees, forms black bootlace-like strands which wrap around the tree trunk just inside the bark.
Hairy Curtain Crust (Stereum hirsutum)
Birch Polypore (Piptoporus betulinus) grows on birch trees and is also used like the Hoof Fungus for moving fire, but in the past leathery strips were cut from the surface of the fungus and used by barbers to sharpen their razors hence it’s other common name of Razor Strop Fungus.