There are many USB Password protecting tools available on internet. Here is the best one I ever found. It uses advanced sector encryption technology to password protect your USB drive. Also its very easy to use. Just set your password and within minutes it encrypts your data (including your music files, documents, photos and everything) saved on your drive. Many other Software out there takes a long time about 5 mins to encrypt a regular 4GB USB drive. But with this software it takes few seconds to both encryption and decryption your data. I personally use this Usb Protection Software to password protect my 64GB Kingston Data Traveler and it only takes few moments to do so. So if you want to try this small powerful tool, download it from here.

:)
Cheers,
Frank Dushan.