If you are looking for a quick way to encrypt your data in USB Flash Drive, then you have come to the right place. Ofcourse TrueEncrypt can also solve your problem, but I believe it is mostly towards permanent external hard drives. For quick encryption, try out UniSoft Removable Storage Protector. It is a free tool that runs from the system tray and can encrypt all data that is copied to the USB drive.
Unlike other tools, which require multiple steps before you are able to encrypt the data, this requires no step at all. It will ask you to enter the personal key(password) during installation and that is all.
When installation is complete you will find it running in the system tray. You can now copy any file and send it to your USB drive. It uses AES-256 encryption which means that it can’t be decrypted by anybody, unless he/she is a security expert with a supercomputer. The files can only be decrypted on the computer that has Removable Storage Protector installed with the correct password.
Note that it’s main purpose is to encrypts your data, which means that nobody will be able to access it. But remember that anybody can delete the data if your USB drive gets stolen. In other words, it focuses on keeping the data secure forever. The only downside is that it works on USB that has 4GB or less storage. Since it is mostly focused for ordinary home users, I think this limit is ok for the masses.
It works on all versions of Windows. Enjoy!