This blog http://subliminalmanipulation.blogspot.com has quite a bit on 'subliminal' visuals (nothing audio, I think). The easiest to do is airbrush style lettering, with e.g. Photoshop. The visual pun imagery - in the style of the cartoon of the young girl/old crone, or, at an advanced level, some of the works of Salvador Dali - is still quite difficult. http://subliminalmanipulation.blogspot.com/2010/09/new-generation-of-subliminal-messages.html has a collection of images (arranged vertically - scroll down through them). Including the Harry Potter posters, and film sets, typically with the word 'SEX' in them no doubt executed in software.
Includes drawing of foetus or baby
________________________________________________________________
Here's a Youtube http://www.youtube.com/watch?v=h4to2f4L5MU (nearly 2 hours) on subliminal imagery, but with mentions of Eddie Bernays and Walter Lippmann amid the sex, hate, anger, and occasional smiley face. The political stuff is all a bit elementary - Obama with aureoles tound his head, etc. I couldn't find any nuke material anywhere here. Maybe they use this stuff for trainees?
________________________________________________________________
The high-definition of computer graphics now allows another category, related to optical illusions - a photo retouched with anomalous feature(s) - see below for an example. So far these are usually 2-D, but if anyone comes up with a way to provide a different image to each eye no doubt they'll be in 3-D as well.