To shield EM radiation, there are the infamous aluminum hats. A colleague of mine actually tested that and found them to be ineffective as shields, because of the large opening downwards. Now I wonder if meshes are better than foils, because foils can actually reflect radation and a parabolic hat shape would focus incoming radiation right inside your brain. Meshes have closed loops which shortcut currents from induction. Is that better than foils? (Serious question on the shielding, mesh vs. foil, inserious with the aluminum hat example. Answers please on the mesh vs. foil part, not the hat part).
I wear my tinfoil hat so that the insidious... machines... hidden inside my walls can't transmit crazy thoughts into my head. (Reading Sciforums has the same effect.) Yikes! I never thought of that! I'm just a layman, but wouldn't the effectiveness of mesh depend on the wavelength of the radiation? If the radiation has a long enough wavelength that a mesh interacts with it like a solid, then wouldn't the mesh still act like a parabolic reflector?
A solid foil is better at blocking electromagnetic radiation than a mesh with holes. But Yazata is right: as long as the size of the gaps in the mesh are significantly smaller than the wavelength of the radiation you want to block the mesh will do an ok job.
Good to know. I still haven't really made up my mind about the whole electrosensitivity thing, but at times I consider to add a shielding around my sleeping place. Meshes sure would be better suited for that instead of foils, a bit like a mosquito net.