This portrait of Hitler accompanied James Delingpole's article 'Mein Kash: Milking the Third Reich,' written for Esquire UK. The piece examined the publishing trend to release books about Hitler (which number close to 1,000 on Amazon). For such an article, Bar's choice to convert the moustache into a barcode was spot-on.
This is using the Gestalt principle where we are using positive and negative space. The negative space of the coffee cup is actually a person talking and the top of the coffee cup comes out to be a thought bubble.