Perplexcity makes it to front page of News.com

The first advertisement appeared in USA Today a week ago, right on schedule.

People from around the world had stayed up all night waiting for it, talking in chat rooms and online forums. It had to be a clue, they thought. Everything before it had been a clue.

"LOST. The Cube," read the ad, posted at the top of the paper's "Notices" section. "Reward Offered. Not only an object of great significance to the city but also a technological wonder."

The cryptic notice, along with several subsequent ads in The New York Sun, The Times of London and Monday's Sydney Daily Telegraph, are the first tangible signs of a mystery called "Perplex City" beginning to unfold online.