"Steghide is a steganography program that is able to hide data in various kinds of image- and audio-files. The color- respectivly sample-frequencies are not changed thus making the embedding resistant against first-order statistical tests." Way-cool technique for encrypting data.
But I still MUCH prefer the idea I came across a year-or-so back which involved encrypting information into spam. You then release the encryption program for general usage.
That way the spooks would then have to closely examine all that spam for messages; pretty soon they would create pressure for spam control measures.
End result: less spam!