These are some Birch polypore (Fomitopsis betulina) fruitings that I found while on a walk today. Birch polypore has been used for thousands of years, evidenced by samples of it being found along with the 5,300 year old mummy of Ötzi the Iceman (https://en.wikipedia.org/wiki/%C3%96tzi). The fungi can be used to fight parasitic whipworm (Trichuris trichura) as well as help seal wounds after being ground into a powder and mixed with water into a paste. Dried samples can be used to sharpen knives as well.