Listen Ms. Sally Citizen, I honestly doubt that anyone in their right mind wants to steal your hundreds of cat pictures and cheesy animated gifs from your USB flash drive, but I guess I can understand your concern. So here you go, protect all of that stupid crap on your USB flash drive with the Cruzer Profile. It uses fingerprint protection and can also restrict access to read-only, prevent access entirely or just prevent copying of data. It is available in 512MB and 1GB models with prices starting at $80.
Sandisk promotes fingerprint protected "Cruzer profile" [PhoneyWorld]