2Pix

2Pix integrates with Windows to allow you to easily encrypt and hide files in bitmap images, a process called steganography (not to be confused with stenography). Data is stored in the low-order bits of each pixel of an image, so the file is completely hidden from view. Version 1.1 now provides plausible deniability because no unencrypted signature is stored in the image header. It should be impossible to prove an image contains a hidden file (if you use a strong password and only use 1 or 2 bits per pixel component).

Features
Integration to right-click menu in Windows
Encrypt files using Rinjdael before hiding them
Secretly hide any file INSIDE a bitmap image's low order bits
Plausible Deniability - Impossible to prove and image contains a hidden file