I use a Corsair Padlock 2 to carry around confidential date such as banking passcodes etc, not to mention passwords for client sites etc.

You've got to remember that the information is no more secure than the systems you plug it into. But for me it's a good way to carry sensitive information with worrying the information is easily read by someone finds it dropped or lost somewhere.

Corsair's Padlock 2 web page



PS. There is a battery inside that powers the button logic. It charges whenever the Padlock 2 and if the battery completely runs down you have to plug it for a few minutes to recharge but there is no data loss.