Like we said this morning, the US starts issuing RFID passports today. Here's the cutest way yet to block RFID signals, even if they won't fit travel docs. These Hello Kitty card covers are designed to stop skimming of the radio-based signals in credit cards and subway passes (more popular in Japan than here). We feel safer, and warm all over. The set of four costs 6,300 or US$55.