SAN DIEGO (CBS 8) - A fierce battle is raging between the occupants of two buildings on Canal Street in the Soho neighborhood of New York City. But this is a friendly battle and the weapons of choice are Post-it notes.

Employees of different creative agencies and media companies based in the two buildings are competing to create the most elaborate and colorful designs on their building's windows using Post-it notes.  

The game started when an employee at one of the companies posted the word "Hi" on a window. Soon after, employees across the street responded with their own designs, which led to a back-and-forth exchange, leaving the windows of both buildings full of Post-it note designs.

The so called "Post-it note War" has been a big hit on social media and has its own hashtag named for the street where the two buildings are located: #canalnotes.

The Post-it note war has even caught the attention of the company that makes them, giving them cause to send boxes of Post-it-notes to the various firms to keep the war going.