From Cybertron Software:
Privacy Drive is an easy-to-use encryption software that uses Virtual Disk & “On-the-fly” Disk Encryption Technology to lock, hide and encrypt all kind of pictures, videos, documents, files and folders, password protects sensitive information from unauthorized access. Using industry-leading strong encryption algorithms, Privacy Drive allows you to create multiple encrypted volumes to mount as virtual disks, you can use them just as other normal hard drives. All data on the virtual disks is stored in encrypted form and is automatically encrypted or decrypted right before they are saved or loaded, you don’t need to manually encrypt or decrypt each and every file or folder.
When you are done, simply dismount the virtual disk/encrypted volume and all your important files and documents will be instantly protected. There is no data stored on an encrypted volume can be read (decrypted) without using the correct password. The entire file system within the volume is encrypted (e.g., file names, folder names, contents of every file, free space, meta data). Furthermore, you can transfer your encrypted volumes via email, upload or backup, move or copy them to external hard drives, USB drives, Firewire drives, CD/DVD, Cloud Servers (such as Microsoft SkyDrive or Google Drive) or any other portable storage device and take them with you, wherever you go, you can continue to access your encrypted data using Privacy Drive. This gives you the power of taking your sensitive data anywhere you want without the fear of data loss or theft.