Re: An old but solved problem
"Is there not a program which conceals the encrypted message within a jpg or other image file?" -- Donchik.
Yes, there are several --- search "Steganography." More to the point, if you conceal it within an original creation of your own (i.e. there's no way to compare the picture to an 'original version' out on the web) you can post it publicly on Facebook, Tumblr or any number of well known places and, providing you have enough friends/watchers then they cannot even see to whom it is addressed.