http://www.rfidjournal.com/article/articleview/2361/1/1/
Jonathan Collins
"To bolster data security, SmartCode's tag design has a button that must be pressed to make the tag operable. Israeli RFID systems provider SmartCode says it has developed an RFID tag with a switch that users would need to activate before the tag could transmit data. The company aims to provide a low-cost way to prevent RFID-enabled passports and ID cards from being skimmed (having data pulled from the RFID tag over an unauthorized connection) while in a holder's bag or pocket."
