Cipherlok

From the developer: "Cipherlok is a data security product that provides easy to use yet highly secure encryption of files on your PC or notebook using the Blowfish algorithm. Files or folders can be encrypted directly by right clicking them within Windows explorer and selecting Cipherlok. Files can also be assigned to be automatically encrypted at shutdown and decrypted at startup ensuring security when, for example, travelling with a notebook computer. A secure file delete function ensures that deleted files cannot be retrieved. Cipherlok works either with traditional passwords or for extra security can use our USB Cipherlok Tokens."

Limitations:

30-day trial