Methinks it's Subliminal

A giant billboard down the street from my house:The snake seems overly ... erect.
The only thing I remember from grade 10 English was the class where our teacher showed us actual examples of subliminal messages in magazine ads. His examples included a woman drinking from a glass that had a reflection of a penis airbrushed into it and various ads for booze/cigarettes that had words like death, alone, sex, f*ck and c*nt embedded in them if you knew where to look. The art of persuasion indeed.