TrueCrypt v4.2a
TrueCrypt is a software system for establishing and maintaining an on-the-fly-encrypted drive. On-the-fly encryption means that data are automatically encrypted or decrypted right before they are loaded or saved, without any user intervention. No data stored on an encrypted volume can be read (decrypted) without using the correct password or correc…
This is an open source programs I use everyday. I think it is essential for your sensitive data if you still run your laptop with XP Home.