Mystery signpost snatcher | Fun with fungi | Programmed to empathise | Chris Mullen’s career | Give up the ghostRe the signpost snatcher (‘Phantom post snatcher’ on Snowdonia Slate Trail wrongfoots ramblers, 22 August), I once saw, in the house of a keen walker, a lampstand made from a wooden waymarker. So there could be a market for such things. Margaret Squires St Andrews, Fife• The recipe Phil Gates retrieved to produce ink from inkcap mushrooms (Country diary, 16 August) is a great example of the value of fungi. And it’s not just ink: research is under way to produce textiles, paper, insulation and other materials from mushroom species. Perhaps a mycological version of the Guardian isn’t far off. Keith Thomas University of Sunderland Continue reading…