Aye, and just to be safe, wear tin foil on your head in case their scanners can get your PIN number from your brain.

NFC? Got it on my Apple Watch. I have to be just about touching the card machine for it to register. The completely different system on my credit cards is about as strong. To be fair, I keep my Oyster Card apart but that's because two or more signals means none register, it doesn't mean they all register.

Next.