Back in June, Edwin covered One Million Checkboxes, a website with one million checkboxes that players could check or uncheck, with any change visible to all other visitors of the site. It became an obsession for some in the two weeks the website was online, as players fought to fill all the boxes, or undo the work of their peers.
The fight was far more complicated than it seemed, as the developer recently explained, with some players finding ways to encode hidden messages in the checkboxes.