If you feel as though you're seeing QR codes everywhere, you're right. The little black and white pixilated squares are suddenly ubiquitous, not only on print ads and bus posters, but on banana labels, wine bottles, takeout coffee cups and pet ID tags. You can get mini QR stickers for your fingernails and temporary QR tattoos – even an awesome Guinness Beer glass that shows the code when the dark liquid is poured in.

While marketing experts remain divided as to the effectiveness of QR codes, Google has found a way to use them in a powerful cross–marketing campaign. The company has distributed thousands of window decals to US businesses, declaring “We’re a favorite place on Google”. These decals include a QR code that leads to the business’ mobile Place Page on Google, where you can read reviews, find special offers, or leave a review of your own. The idea is pure win-win: What ambitious business wouldn’t want to be associated with Google? And as if it wasn’t ubiquitous enough, now the Google name is visible on thousands of street-level windows on the streets of America.