My friend has a USB sort of like that. Instead of scanning thing like "facial features" and "Skin tones" it copies the history and anything you've ever typed into a computer that is saved on the hard-drive.
This includes paypal account information, credit card numbers, and steam passwords. He didn't get anything from me, bur I guess it's because I never keep anything, but my other friend spent an hour changing any information he could because he was paranoid.
My friend with the USB was mearly causing havoc at our Lan party, and wasn't being malicious.