RFID SHIELDING PASSPORT POCKET
Modern credit cards and passports contain small RFID chips that allow them to be scanned/read to interact with payment terminals (PayPass etc for credit cards).
While this technology is terrific it is possible for this information to be skimmed illegally and like pickpocketing might be more of a problem when travelling.
I use Cobaltex® (a RFID shielding fabric I've sourced from the USA) to add an extra lining to the internal pocket where you might keep your passport, wallet etc to protect against having your details stolen.
You can find out more about Cobaltex® here.