Rival ad agencies in opposing New York City office buildings are trying to stick it to each other — in the form of Post-its.
Sticky notes arranged in colorful patterns or spelling out messages have covered window fronts along lower Manhattan's Canal Street. The unusual battle — chiefly between ad firms but since spreading to other companies in the buildings — has prompted passersby to take notice of the Post-it tit-for-tat.
The first message was spotted last week when someone at the firm Horizon Media wrote, "Hi," according to reports.
Then, an employee at Havas Media shot back: "Sup."
And from there, the window wars heated up, spawning the hashtags #CanalNotes and #PostItWars — and inspiring office workers around the world to rise up from their cubicles and mount similar challenges.
The staff of Sandbox Studio and its parent company, Creative Drive, put up a Marilyn Monroe-inspired Post-it Tuesday from its office windows in Manhattan.
"We are a photo studio, so we wanted to do something more creative, which was why we went with a piece of art," employee Andrea Raymer told NBC News.