Interestingly, there is now a common product available (Faraday bags and wallets, for wireless device / RFID security) that actually achieves the intended goal

Interestingly, there is now a common product available (Faraday bags and wallets, for wireless device / RFID security) that actually achieves the intended goal of tinfoil hats. I would absolutely wear a beanie / knitted cap made from these materials, even though I’m not at all worried about radio signals affecting my brain.