Program: TrueCrypt
License: Open Source/GPL
Description: A program that create a file that act like a new volume that is encrypted, needing a password to get access.
Website: http://www.truecrypt.org/
It already is a portable software, that can be unpacked inside a usb drive, but it needs admin rights to function. It could be nice if we could use it integrated with PortableApps and whithout needing admin rights.
thanks