I've seen some really complicated USB/File encryption programs, but the reality is- all I want is a small program that is loaded on your USB stick and auto runs automatically asking for your password when the stick is inserted into a USB port. Unless you provide the password, the drive remains unrecognized and is unusable to view, write or read from etc. So the key is to keep Windows from recognizing and assigning a drive letter until a password is entered.
Hopefully this will also prevent programs such as explorer from reading the contents on the drive. Heck, I don't know how many USB devices that I have that the opposite is already true. My computer doesn't recognize my drive and I can't get anything off of it no matter how hard I try, or mess with the USB device drivers!